Archive for the ‘Vegetables’ Category

Sow Cool Season Plants in Summer for a Fall Crop

Two harvests in the same growing season are easy to accomplish. Many gardeners sow and plant in spring, spend summer tending to their crops, harvest in early fall, and then wrap it all up and wait until spring to repeat the same process. With little effort you can double your garden’s output with sow, tend, sow, harvest, tend, and then harvest again. Then you can spend winter satisfied that your garden played double duty to produce all it could.

Grow chard to harvest in fall

Grow chard to harvest in fall

In late summer you sow seeds for cool season plants that will grow as temperatures begin to decline. They’ll be ready to harvest after the first frosts have appeared and long after the last tomatoes were pulled from the vines. There is no need to create new gardens; you use the same beds you do now.

Cool season crops are primarily the ones that provide leaves, stems, and roots for harvest. These crops include:

Arugula, beets, broccoli, Brussels sprouts, cabbage, carrots, cauliflower, celery, chard, collards, endive, fennel, kale, kohrabi, leeks, lettuce, mustard greens, onions, peas, parsnips, potatoes, radishes, spinach, turnips

Peas, especially, snow peas do well in cold

Peas, especially, snow peas do well in cold

Many gardeners grow these plants in spring and hope for a slow start to summer so the plants will mature and be ready for harvest before high heat causes them to bolt and their taste turns bitter. We take advantage of their natural ability to tolerate low temperatures by planting early.

We can also use that ability to plant late. The mature plant tolerates the low temperatures of fall, there is no risk of bolting, and many people believe many of these crops taste superior after exposure to frost.

Those of us who sow in early spring and hope the soil has warmed enough to initiate germination are ready for a percentage of our seeds to never grow. Those of us who sow in late summer are pleased that the warm soil provides speedy germination with little seed loss.

Early seed and plant care is different when you plant late. In spring there is less need for extra watering; lower temperatures mean less evaporation and there is always a chance of rain or late snow. In summer, the heat requires more gardener attention to maintaining moist soil conditions for seeds and young plants; you may need to mist or water the plants two or three times a day in harsh sun.

Temperatures above 80F (27C) will cause broccoli and spinach to bolt quickly. Sowing in a shady spot or setting up a row cover can reduce this concern.

Once the plants have a few sets of leaves the need for watering becomes less than in late summer. While early plants need more water to combat the increasing summer heat, later plants require less water as the decreasing temperatures bring comfort. The plants are less stressed in fall. They grow in the conditions they like best; they’re called cool season plants for a reason.

As long as the day temperatures remain about 10 to 15 degrees above freezing (40F – 50F, 4C – 10C) you can expect the crops to continue growing and producing. When the day temps remain below 40F (4C) the plants may begin to suffer. Careful harvesting will still produce results. The center of the plant may still have new, tasty leaves while the exterior leaves look frazzled.

Hard freezes, cold days, and icy conditions will adversely affect most cool season crops and will spell the end for your second harvest, but you can delay winter by mulching heavily with straw and using a season extender like cold frames, cloches, or plastic tunnels. I use my hoophouse system to harvest well into November and even December.

Broccoli and beets ready for overnight protection

Broccoli and beets ready for overnight protection

Some crops like cabbage, kale, and spinach can do well, even in snow. With heavy mulching, beets, leeks, and parsnips can often be overwintered and harvested in spring (I’ve done this).

Use your entire vegetable garden for fall planting. If you have a cool-season spring bed for broccoli, spinach, or lettuce and then let that bed remain filled with bolty, straggly, dried plants throughout the summer, rip those plants out and sow again for a fall crop.

Your tomatoes, peppers, and melons will decline in cooling weather. Anticipate their decline and sow seeds among those plants, in the same beds. When the first frost zaps your tomato plant, cut it out and let the cabbage and broccoli growing nearby overtake that space.

Root crops won’t be as big as spring plantings, but may be tastier. Try growing small, thumb-sized carrot varieties or harvest them young before the ground freezes. Beet roots will be harvested when they’re just a few inches big, but the beet leaves can be harvested continually.

Beet leaves are edible and tasty

Beet leaves are edible and tasty

Garden pests can be less of a concern for a fall garden. Many insect pests are less active, if not gone, in fall. The weeds will spend all summer attacking aren’t active in fall. Even deer seem to be scarce as they make their way to find a winter bed.

While growing a second crop in the same season sounds like extra work, it doesn’t need to be. Summer garden beds should be cleaned up before winter so insects don’t have a place to overwinter. That clean up works well to prepare the beds for fall crops.

You’ll spend a few more days in the garden watering and harvesting, but is that really a bad thing? Fall gardening allows you to do more of what you like and for me that’s a good thing.


The Best Tips for Growing Tomatoes

Tomatoes are the number one home garden crop in the United States. As a result, tomatoes are the home crop that can cause the most trouble for gardeners; something is always wrong with our tomatoes. We all want the perfect tomato, but getting it to harvest can be troublesome. Here are a few tips to help you get the most from your tomato crop by understanding more about this wonderful red (or orange, purple, yellow, or green) orb.
1. Tomatoes are either determinate or indeterminate.

Not all tomato plants are the same so it’s important to know what kind you’re growing. Determinate tomatoes are also called bush tomatoes. They seldom grow more than three or four feet tall and often don’t require any additional staking or support. All of the fruit reaches maturity at about the same time so the harvest will only last over a period of a few weeks. If your plant suddenly stops producing flowers and fruit, even when everything else is perfect, it’s probably a determinate variety.

Indeterminate tomatoes may also be called vining tomatoes and can grow as much as eight feet tall. They don’t produce fruit all at once but rather they provide fewer fruit at any one time, but over a longer period of time. Indeterminate tomatoes will usually give you a harvest until the first frost in fall.

How you grow these different types of tomato can impact how successful you are. For container gardening, like in pots on a patio, determinate tomatoes are the way to go; indeterminate ones can quickly overrun your space. If you like to “put up” tomatoes in quart jars or as tomato sauce, determinate plants will provide a harvest that you can can right away. If you like to have a few tomatoes to enjoy with your meals throughout the summer, indeterminate is the way to go.

Determinate tomato plant

Determinate tomato plant

2. Select the best heirloom or hybrid tomatoes for your garden.

Many gardeners believe heirloom tomatoes taste better than hybrids. That can be a matter of personal preference, but there are other obvious differences between the two. Typically, heirloom tomatoes have more problems with diseases and pests; hybrids have been developed to overcome these limitations. Heirloom tomatoes tend to take a long time to reach maturity and harvest; hybrids can be selected with very short “days to harvest”.

If you have a garden in an area susceptible to tomato diseases, you may want to select a hybrid tomato with letters after its name (like VFN); the letters identify resistance to disease. If you garden with a short growing season, you can select hybrid varieties that will ripen early.

Hybrids tend to follow a pattern of red, round fruit. If you want to grow purple, orange, yellow, or striped tomatoes, you’ll probably want to look for unique heirlooms. Determine what you want in a tomato and then find the variety that fits, whether its heirloom or hybrid.

3. “Days to Maturity” and “Days to Harvest” are important.

Seed packets or plant tags should give you an idea of how long it takes the plant to reach harvest. That is the number of days from the time you put the transplant in your garden, not the time from when the seed was placed in soil. Even a robust plant from a nursery can take more than two months to provide fruit. If you garden in a region with late springs and early falls, you may only have about four months to adequately grow tomatoes (my season is about 134 days). If you select an heirloom plant that takes 120 days to harvest, there will only be a few weeks for harvest before the first frost and if it’s an indeterminate plant there will still be many unripe fruits on the vine when cold hits.

Match the plant with your garden for best results. A tomato that takes “80 days to harvest” can provide fruit for two months more than an heirloom beefsteak tomato. Of course, if you have a very long growing season your choices are virtually endless.

4. Tomatoes need sun and air.

Selecting the proper location for your tomatoes can make the difference between healthy plants and sickly ones. Tomatoes need full sun; that means at least 10 hours a day and more is better. Even a little afternoon shade can have a big impact on plant growth and harvest. Of all your garden plants, tomatoes should have the sunniest spot.

Many of the disease, virus, and fungal problems that plague tomatoes can be corrected by increasing airflow around the plants. Don’t plant too close to other plants. With air circulation the leaves can dry out and not fall prey to the diseases that require moist conditions.

Disease can be reduced

Disease can be reduced

5. Garden soil needs to be warm to plant.

Tomatoes are a warm season plant and need warm soil and warm nights to begin growing. If planted too early, the plants can be stunted and even killed by cold soil temperatures. Some gardeners recommend planting when the air temperature remains above 50F degrees (10C), but that may be troublesome because the soil temperature at root level, six inches and more, can still be below that. Research has found that the best soil temperature is 70F; tomato roots will not grow at all below 50F.

I recommend waiting a few weeks after your last frost date to put in transplants. I also suggest using a temperature probe in your soil. Wait until the soil is closer to 60F to plant; at least 55F. You can accelerate soil warming by covering your garden bed with a plastic sheet for a few days before you plan to dig.

Check soil temperature

Check soil temperature

6. Well-drained soil is nice, but amended is better.

Tomatoes do best in amended soil. A well-drained soil is nice to avoid pooling water, but if the water drains too quickly the plant and fruit can suffer. Tomatoes will grow in clay soils as long as they don’t remain soggy. The best way to correct poor soil is with organic amendments like compost. A loose, healthy, amended soil will grow bigger and better tomato plants.

7. Pinch off flowers and fruit when you plant.

Many gardeners select young plants with flowers or small fruit on them when looking for tomatoes in the belief they’ll get fruit faster; nurseries grow and price them accordingly to entice you. You can actually delay the development of future fruit by choosing a too-mature plant for your garden.

The main role of the plant is to produce fruit and it will expend most of its energy to that task. However, for new transplants root development is the most important task. If you put a plant with flowers and fruit in your garden bed, root development will be reduced while the plant focuses on ripening the fruit. That means that your plant may not be strong enough to handle the heat of summer and all remaining fruit development can suffer. You’ll get a better harvest if you let the plant grow strong in its early days

8. Bury the plant when planting.

Tomatoes can grow roots along the stem and you should use that ability to your advantage. More roots tend to make for a stronger plant. Placing the plant in the soil with more stem buried than in the original pot will ultimately provide better results.

Pinch off lower leaves next to the stem, leaving the top four to eight groups of leaves at the top. If you have amended soil in a region with steady rain, place the plant vertically in a deep hole with only the leaves above the surface. For poorer soil and in regions where your irrigation may be the only water source, place the plant in a slanted trench so that the stem is horizontal; you can gently bend the top towards vertical and hold it in place with a small soil berm.

Bury deep

Bury deep

9. Tomatoes don’t need as much water as you think.

Consistent moisture levels are more important than amount of water. Many gardeners think of tomatoes as tropical plants that need watering every day. Diseases, blossom end rot, and cracked skins can be the result of poor and inconsistent watering practices. Frequent, light watering can result in poor root systems.

Tomato soil should be moist all the time, but not wet or soggy; think of the moistness of a wrung-out sponge. With amended soil you may only need to water every three of four days. Of course, very hot and dry conditions will require more watering, but physically check the moisture level of the soil before assuming more is needed.

10. Overhead watering can encourage disease problems.

When you water, try to avoid sprinklers or hand watering from above. Almost all of the diseases that affect tomatoes are soil borne. The fungal spores and bacteria are just waiting for a way to reach low leaves and splashing water is the perfect mechanism. Even a drop of water falling from a lower leaf can release these tiny organisms from the soil surface and infect the plant.

Drip irrigation and soaker hoses can drastically reduce tomato diseases. These watering methods get water directly to the roots without any of the nasty side effects of overhead watering.

11. Mulch can help produce perfect fruit.

Mulching with a light, organic material can reduce the problems with soil and watering. Mulch helps to maintain a more consistent soil moisture level. Mulch also acts as a protective barrier so any water falling off the plant hits mulch and won’t release soil-borne pathogens.

I like to use straw or herbicide-free grass clippings for tomato mulch. The light material allows air and water to reach the soil while helping to keep soil temperature and moisture more consistent. It will also decompose and amend the soil for the next season when I till it in at the end of the year.

12. Fertilizer may hurt your harvest.

Proper fertilization is critical to getting a harvest and improper fertilization may result in no harvest at all. With rich, amended soil you may not need any additional fertilizer. If you do fertilize, you need to do it differently at different times.

As mentioned above, root development is important for young plants. Adding a fertilizer high in phosphorus to the soil at planting can help in that development. As the plant grows and nears fruiting, a potassium fertilizer will help in fruit development.

The problem most gardeners encounter when fertilizing tomatoes is by using a fertilizer high in nitrogen. Nitrogen encourages big, bushy plant growth at the expense of flowers and fruit. If you fertilize and get a beautiful plant with no fruit, this is probably your problem.

Look for a fertilizer with higher numbers in the second and third position. The numbers on a bag or box of fertilizer represents the percentage of nitrogen-phosphorus-potassium (N-P-K). A higher first number will spell doom for your harvest. You’ll find specialized tomato fertilizers with ratios of 3-4-6, or 5-6-5, or 4-7-10, or 18-18-21. Note that the first number (nitrogen) is never the highest. In my opinion, better tomato fertilizers would be 15-30-15, or 6-24-24, or 8-32-16.

13. Heat can reduce harvest.

If days and nights get too hot, tomatoes will drop blossoms and no fruit will form.  Tomatoes grow best when the temperatures are between 70F and 90F degrees. When day temperatures are above 95F, or night temperatures remain above 75F, fruit won’t develop. You can take every step above, but if it’s too hot in your garden you won’t get any tomatoes.

14. Pinching suckers may not always be the best idea.

Many gardening “experts” say to pinch off all suckers that develop in the crook between the main stem and branches. While this won’t hurt the plant, it may not be as necessary as proposed. The key is knowing whether the plant is determinate or indeterminate.

Indeterminate tomato plants can get very big. Pinching the suckers can focus growth where you want it so the plant doesn’t become too cumbersome while focusing plant energy for developing large fruit along main branches. Leaving the suckers on the plants will produce more foliage and potentially smaller fruit. Because the fruit is produced over a longer period, allowing it time and energy to grow big may be beneficial. Fewer, bigger fruits can be a good thing.

Determinate tomato plants don’t require any pruning and removing suckers can actually reduce harvest. Tomatoes can develop on the branches that grow from the suckers. Because a determinate plant produces all of its fruit at the same time, more branches and more flowers means more fruit. For many gardeners wanting to preserve their tomatoes, more may be better than bigger.

15. Use a strong trellis.

There are many options for trellising tomatoes and it’s worth spending the time and money for a sturdy one. While a single metal rod or flimsy wire cage will support a young plant, a mature indeterminate plant loaded with fruit will soon flop to the ground, damaging fruit and exposing the plant to all of those disease-causing soil pathogens.

I like to use heavy-gauge steel cattle panels to form a curved trellis over the entire bed. Home improvement centers sell steel lattice panels used for reinforcing concrete; these can be cut and bent into strong towers to support tomato plants. 4 x 4 wood posts set in the ground can be used to train vines on strong wire strung between them. Whatever you use, ensure it can handle the weight of a big plant.

Use a strong trellis

Use a strong trellis

16. Rotate the location of your tomatoes.

As mentioned earlier, the pathogens affecting tomatoes reside in the soil. Once a plant is infected the soil is infected. Continuing to grow tomatoes in that same location the next year means that those new plants are very likely to be infected.

If your garden space allows, it is best to avoid planting tomatoes in the same bed as recent tomatoes. Time will dissipate the pathogens’ viability. Wait at least three years between plantings in the same bed. Ideally, wait at least seven years between plantings. The more you can rotate with longer periods between, the less likely you are to encounter the same diseases.

17. Harvest before the fruit is overripe.

Tomatoes should be harvested when they’re ripe but before they soften. Left too long on the vine, tomatoes can become mushy and bland. Green tomatoes can continue to ripen after they’re picked. For that reason it’s better to pick a little early rather than a little late.

The fruit may crack or develop circular rings near the stem when they’ve been left on the plant too long. Because the fruit often grows in clusters, you can use these signs on one fruit as a signal to harvest nearby fruit.

As indicated by these tips, tomatoes can be a finicky crop. A little too much water, a little too much heat, and a little too much fertilizer will affect your crop. I grow in a very challenging environment and I regularly meet gardeners unwilling to try tomatoes again after a disappointing season or two. It can be a challenge, but there’s a reason tomatoes are the number one home garden crop. When you do it right, few other garden crops can be so satisfying.

Home Garden Crop Rotation

Growing the same crop in the same location year after year can deplete essential soil nutrients in that area, subject plants to harmful diseases, and adversely affect the crop’s growth, health, and production. To avoid this, for thousands of years farmers have practiced two, soil-enhancing, growing methods. The first is allowing a field to lie fallow. Periodically after harvest, plants are turned into the soil and allowed to decompose for a year; essentially it is in-place composting.

The second method is crop rotation. Different crops are planted in different years in a single field. For home gardeners, allowing a garden to remain unplanted goes against the very essence of why we garden so practicing crop rotation to prevent a cycle of diminishing harvest is the best idea.

Crop rotation is used to keep soil from losing nutrients that a specific plant needs. A plant like corn needs a lot of nitrogen from the soil. When it is planted in the same spot repeatedly, it will ultimately deplete all available soil nitrogen, committing a slow suicide. On a commercial level, farmers add tons of nitrogen fertilizer to soil to artificially feed the plants. On a local level, home gardeners add nitrogen fertilizer to their soils when they notice reduced plant growth too.

Effective home garden crop rotation can drastically reduce the need for supplemental fertilization and helps maintain a healthy, balanced, nutrient-rich soil. For organic gardeners it is almost a must.

Each year my garden looks different with crop rotation

Each year my garden looks different with crop rotation

The concept of crop rotation is simple. Crop A is planted in year one, Crop B is planted in the same location in year two instead of Crop A, Crop C is planted in year three instead of Crop A or B, and so on until the cycle is repeated.

The simplest cycle is a two-crop rotation where a plant like corn is planted one year and a crop like peas is planted in the same bed the next year. Then the cycle repeats each year with corn followed by peas followed by corn followed by peas; each cycle is completed in two years. A three-crop rotation takes three years to complete. A seven-crop rotation takes seven years.

The selection of the plants for each year is the most important aspect of crop rotation. To be effective, each successive planting should grow differently than the previous planting. In the two-crop example above, corn grows in a spot, depleting soil nitrogen. The next year a legume like peas is planted to replenish soil nitrogen. Many legumes have root nodules that harbor beneficial bacteria that takes nitrogen from the air and fixes it into the soil.

Peas are producing with plenty of space for new seeds

Peas are a perfect legume to plant

In a home garden, legumes are a great choice in an easy crop rotation cycle. Peas, beans, lentils, and soybeans provide a nice harvest while adding nitrogen to soil. Other plants like clover, alfalfa, and vetch don’t offer a harvest, but have the same beneficial properties. I use vetch in my garden as part of my crop rotations; the vetch is attractive with pretty little purple flowers. After a season of growth that fixes nitrogen into the soil, the plants are tilled in to add additional organic material.

Vetch looks good and adds nitrogen to soil

Vetch looks good and adds nitrogen to soil

I like to practice a three-year crop rotation in my garden. In recent years I’ve done a tomato-pea-cucumber cycle, a garlic-pea-spinach cycle, and a beet-bean-cucumber cycle. In each of those cycles I also grew vetch. Vetch can handle cold weather so I sow it in fall after I’ve harvested and cleaned up a bed. The vetch grows into winter and again in early spring; I turn it into the soil about six weeks before planting the new season’s crops. For plants with early summer harvest, I’ll sow vetch and allow it to grow during the remaining summer and early fall.

A basic three-crop cycle of sowing plants that produce nitrogen, followed by plants that are heavy nitrogen feeders, followed by plants that are light feeders is easy to start.

A four-crop cycle is also easy if you divide plants into groups. Fruiting plants like tomatoes, cucumbers, and pumpkins is one group. Leafy plants like spinach, kale, and broccoli is a second. Root vegetables like carrots, beets, and potatoes is a third. Legumes like fava beans, peas, and lentils is a fourth.

Another important reason to rotate your crops is to reduce disease and pest problems. Tomato plants are very susceptible to soil-borne pests and pathogens. In the first year of planting a new bed, tomatoes often do very well, but after being in the same spot for a period of years they suddenly seem to have problems with early blight, fusarium wilt, or leaf spot. The fungus or bacteria that causes many potential tomato problems lives in soil.

Once a plant is infected it spreads that pathogen into more soil. Any new plants in the bed will become infected and help spread it further. Crop rotation breaks this cycle. An infected plant may adversely affect soil, but if there is no new plant to spread the fungus, bacteria, or virus, it will eventually diminish and no longer cause problems.

Tomatoes with problems can infect soil

Tomatoes with problems can infect soil

This works because the pathogens are plant specific; tomato disease will not affect corn, peas, spinach, or pumpkins. Crop rotation helps keep plant problems from becoming established in your garden. Before tomato pathogens develop, another plant like beans grow in the bed, then a plant like spinach is planted before bean problems develop.

Knowing what plants you want to grow and the most likely diseases in your region will help you determine the best cycle. Many fungi that affect tomatoes remain viable in soil past three years so a four-crop rotation is recommended. By the time tomatoes are planted again, the threat is gone.

It’s important to be aware of plant families when planning and planting. Tomato, eggplants, and potatoes can be susceptible to the same pathogens. Tomatoes and peppers have similar problems. For that reason similar plant families should not be included in a crop cycle; avoid planting tomatoes and peppers or tomatoes and potatoes in the same bed within a single crop cycle.

I practice a three-crop cycle because it’s easy to plan and easy to do. It reduces the potential for problems, but isn’t foolproof. If I do encounter problems in a bed, like tomatoes, I’ll make note and transform that bed’s cycle into a four-crop or five-crop model.

Occasionally I get lazy or behind in planting and repeat crops in a bed. Problems don’t automatically develop, but I do try to get back on track for the next year.

Only perennials like rhubarb stay in the same spot

Only perennials like rhubarb stay in the same spot

For virtually flawless results, a seven-crop cycle can be followed. There are very few pathogens or pests that will survive seven years in soil. Extra effort should be taken to insure adequate legumes are added in the sequence. If you have the space and the inclination to develop this more-complicated cycle plan, seven is the magic number.

Home garden crop rotation also provides a great opportunity to amend your garden soil. Because you’re cleaning up each bed before planting a new crop, the addition of compost is easy to do as part of soil preparation before sowing or planting. Tilling in the spent plants from the previous season, like I do with vetch, also adds important organic material to soil.

The combination of crop rotation and soil amending acts to maintain a healthy soil environment. Beneficial soil bacteria and organisms thrive while harmful ones diminish and the microorganisms help make soil nutrients available to plants, enhancing overall garden production.

It does take a minimal amount of extra time to plan and initiate a new crop cycle. Depending on the size of your garden you may have to forgo certain crops in some years if there isn’t enough space for a complete cycle for all garden plants. I accept these limitations as a tradeoff for a better garden overall. Occasionally doing without chard or parsnips or butternut squash is okay.

Home garden crop rotation is easy to do and has many benefits. While you’re planning your next garden, think about doing it a little different than last time.

Biochar Works in the Garden

Biochar enhances plant growth and is ideal for short-season gardens.  In my experimental garden bed, biochar added an extra two weeks to my harvest schedule. For many of us who grow in challenging regions, that can be more than 10 percent of our growing season.

Biochar is reported to improve the development and growth of plants. Most of the benefits have been reported through anecdotal evidence so I decided to conduct as scientific an experiment as I could to prove or disprove the claims. I’ve written about biochar before and about the beginning of this experiment (see my article “Using Biochar in the Garden“, June 4, 2012).

I was convinced by others on the internet that biochar could improve my garden, but I wanted to prove it to myself, and others looking for statistical analysis. With a calendar, metric ruler, and scale, I set out to document the effectiveness of biochar. I must acknowledge that a new friend, the daughter of very good friends, is a strong advocate of biochar and is a director at Soil Reef Biochar, a company selling and marketing the product. That had no effect on my analysis.

Using 100 percent biochar from Soil Reef Biochar, I amended the soil in one half of a four feet by eight feet raised bed. As a control effort, the other half of the bed remained unamended, aside from an addition of compost that the entire bed received one year earlier. As mentioned in my earlier article, I inoculated the biochar with beneficial bacteria. After amending the soil I let the bed rest for three days, keeping the bed’s soil moist in the process.

Amending with biochar

In each four feet by four feet half I placed 24 ‘Straight Eight’ cucumber seeds at the recommended depth, spaced approximately six to eight inches apart in a grid. ‘Straight Eight’ is a common slicing cucumber that I’ve had success with in the past. Normal germination ranges from 3 to 10 days with about eight days being the norm. Maturity is reached in about 50-75 days with about 60 days being the norm.

The growing season in my garden at 7500′ elevation (2285m) is short, typically ranging from 110 to 130 days. Late frosts are common in spring and delay sowing and planting of warm season plants. My seeds were sowed on May 30, 2012, and I began the diary of plant development at that point.

The first obvious difference in the biochar side of the bed began with the germination time and rate. On June 3, five seedlings broke the soil surface. That is four days after placing in the soil, half of the typical germination time. The first non-biochar seedling appeared on June 4, but the biochar germination rates exceeded the other half. Here are the results for the germination of each side:

Biochar seedlings                               Control group seedlings
June 3  (Day 4)                     5                                                               0
June 4  (Day 5)                    13                                                              1
June 5  (Day 6)                    19                                                             13
June 6  (Day 7)                    23                                                             16
June 7  (Day 8)                    23                                                             18
June 8  (Day 9)                    23                                                             19

All of the biochar seeds sprouted earlier than the expected germination time. After nine days, 23 of the 24 seeds sprouted on the biochar side, a 96% germination rate. Only 19 of the 24 in the control group sprouted, a 79% rate. The soil was kept consistently moist on both halves and no pest damage was evident. There is no clear reason for the lower germination rate of the control group.

Cucumber seedlings in the biochar soil

It’s obvious that the biochar plants got an earlier start than the control group and that advantage carried through for the rest of the experiment.

On June 25 (Day 26), I measured the height of all the plants. The average height of the biochar cucumber plants was 7.53 cm. The average height of the control group was 5.34 cm. In an effort to avoid skewed numbers, I deleted the measurement of the smallest and tallest plants in each group before averaging. The biochar plants were 41% taller than the control plants.

Measuring a seedling

At this point I thinned the plants to 14 in each half of the bed. Each section’s plants were staggered in four rows spaced about one foot apart. This spacing is closer than commonly recommended, but not out of the ordinary. It does add a minor stress factor.

All of the plants were watered at the same rate and received addition of a balanced liquid fertilizer on days 26 and 37.

On July 6 (Day 37), I measured the plants again. The biochar plants averaged 16.2 cm and the control plants measured 12.22 cm. The biochar plants were 33% taller than the control plants at this point.

The test bed with biochar on the right

The first flower appeared on a biochar plant on July 15. The first flower in the control group appeared on July 21; eight flowers were on biochar plants at that time. That six-day difference continued the trend of accelerated growth in the biochar plants.

All of the fruit was harvested when it was at least 18 cm (7 inches) long. The average in both groups was 19 cm (7.5 in) at the time I picked them. I harvested the first fruit on a biochar plant on August 10 (Day 72). The first fruit on a control plant was harvested on August 22, 12 days later.

The accelerated growth in the biochar bed allowed me to begin enjoying juicy cucumbers almost two weeks earlier than a standard garden bed in my garden. I harvested four biochar cucumbers before I picked the first one in the control group.

It should be noted that the maturity/harvest point of the biochar cucumbers was at 72 days, at the high end of normal maturity and past the expected 60 days. The control group reached maturity/harvest at 84 days, well past expected maturity. This isn’t unusual in a high-altitude garden. Our summer nights are cooler than gardens at lower elevations and this temperature variation delays maturity of many warm season plants.

The plants nearing harvest

I expected that the biochar cucumbers would be bigger and more robust that the control group, but that wasn’t the case. The average biochar cucumber was 19.14 cm long and weighed 272.2 grams. The average control cucumber was 19.02 cm long and weighed 279.1 grams. The control group cucumbers were about 2.5% heavier, but that isn’t statistically significant with my measurement methods. Basically, the cucumbers in both groups were about the same size at harvest.

A biochar cucumber

Ultimately I harvested 13 cucumbers from the biochar plants and 12 from the control ones. The stress of growing the plants close together reduced the potential number of fruit, but that was partially intentional so I wasn’t overrun with cucumbers to measure. I was also on vacation for 10 days during the middle of the experiment and our house sitters enjoyed a few cucumbers that weren’t measured.

I had the first frost damage to my garden in the middle of September at about 110 days into the growing season. Though I covered the cucumber bed with plastic and was able to keep the plants alive for a few more weeks, the cooler weather effectively ended new growth and flower and fruit development. There were still a number of cucumbers, of varied sizes, on the vine when I let them succumb to the climate.

I think the results of this experiment are clear. Biochar speeds and enhances germination in cucumbers. The earlier germination and effect of biochar in the soil leads to greater plant growth rates. This enhanced growth results in earlier flowering, fruiting, and harvest in biochar-amended garden beds.

Biochar offers a clear advantage to gardeners like me who have concerns about short growing seasons. For gardeners in warmer climates and more gardener-friendly regions, two weeks of extra harvest time may not seem like much, but for me it’s substantial. My tomato beds are almost always two weeks short of reaching full maturity.

We can infer that the results of this experiment with cucumbers can be carried over to other plants in the garden. I’ve started another experiment using biochar in one bed of cool season plants and no biochar in another bed of the same plants. The biochar plants are already larger than the others.

Next year I’ll add biochar to my tomato beds and I anticipate bigger growth and earlier harvests. I plan experiments to determine if the ultimate harvest amounts of biochar beds is larger than non-amended ones.

Biochar adds an exciting component to gardening. As advertised, it does influence the growth of plants in a very positive way. Currently about 10 percent of my garden is amended with biochar. I look forward to the day when all of it is enhanced.

Plant a Fall Crop

Sowing and planting in summer is a great way to get the most out of your garden space. I just sowed beets and broccoli in early August and will be able to squeeze in another crop of vegetables before winter snow and hard freezes put an end to my growing season. The plants mature in fall and provide a nice second harvest. This fall crop allows a garden to produce a full second season.

Beets are a good fall crop

My lettuce and spinach beds were pretty well spent after the plants bolted and went to seed. Many gardeners would clean up those beds and let them lie fallow until spring, but I used that space to plant another crop. That essentially doubles my garden output without increasing its overall size.

The key is understanding the difference between cool season and warm season garden plants. Cool season plants are the ones we usually plant in spring. They include cabbage, lettuce, spinach, kale, peas, radish, beets, and chard. These plants can handle an occasional bout with cold temperatures. Warm season plants are the ones we plant after the last frost date. They include tomatoes, peppers, vine squash, and melons. When those plants experience frost they shrivel and die.

We can sow cool season plant seeds in early spring because the young plants aren’t killed by late frost. Many gardeners know that it takes awhile for many of those seeds to germinate because of cold soil temperatures. When they do begin to grow, their productive season can be short because the heat of summer tends to affect them adversely and they flower, go to seed, and fade quickly.

Sowing these same seeds in late summer results in quick germination in the warm soil. There is no cold threat to the young plants and they grow quickly. As they mature and begin to fruit an occasional early frost may threaten, but the larger plants can shrug it off easily. There is absolutely no threat of high temperatures causing the plant to bolt so they produce fruit until they die.

That’s one of the greatest advantages to planting a fall crop:  the production of fruit is often longer and greater than spring crops. These plants often relish the cool temperatures and rather than respond poorly to hot days they respond richly to cold days. Many people think these plants produce tastier produce after they’ve been exposed to cold.

Treat your second season garden just as you would a spring one. Before planting, amend the soil and prepare the bed. A good dose of compost or aged manure is a nice boost to soil that has already been used for a recent crop. You usually have plenty of time to do this from when the plants fade in mid summer to when you plant in late summer.

I amended one fall bed with biochar

Mulch becomes an important factor in the success of a fall crop. Mulch moderates soil temperature. In a spring planting for summer harvest, the mulch helps keep the soil from getting too warm. In a summer planting for fall harvest, the mulch helps keep the soil from getting too cool.

Be aware of different irrigation needs than you may be used to. The seedlings and young plants are beginning to grow when it’s still hot out. A new spring bed may need watering twice a day to keep the soil moist. A new summer bed may need watering four or five times a day to stay moist. To help keep the soil from drying out quickly, I drape fabric over the bed to shade the soil until the plants establish themselves and the days begin to cool. Row covers and shade cloth are ideal.

A recycled patio umbrella provides shade

Once the plants mature, their water needs will be less than the same plants in early summer. In the cooler days of fall, there is less evaporation and water loss due to transpiration. Mulch can mask the true level of soil moisture so be sure to physically check the soil before you water. Over watering and drowning roots is common in second season gardens.

Be ready for different growing characteristics. When I sowed beet seeds in spring it took almost two weeks for the first sprouts to appear; even cool season plants need the soil temperature to be warm enough to effectively germinate. The beet seeds I sowed in summer germinated after four days.

Many root crops are well suited as second season crops. Carrots, turnips, parsnips, beets, and radishes do well when planted up to two months before the first frost. For me that’s early August, but for many gardeners that time extends into September or October. A thick mulch helps keep the ground from freezing early and affecting the growth and harvest of the roots.

Cabbage, green onions, spinach, cauliflower, snap and snow peas, should be planted a little earlier to ensure they complete their growth before cold sets in. For me that was mid July, but for many gardeners that time is now.

Tough greens like endive, mustard, chard, spinach can handle cold well. Chard, in particular, grows in snow and has a nice sweet flavor as a result.

Second season gardens offer advantages that are easy to overlook. The cooler temperatures affect weeds and garden pests too. Less weeding and pest management chores are definitely welcomed by most gardeners. Often, it isn’t until you’re reviewing the success of your growing season with the snows falling that you realize how easy the fall crop was to maintain.

When you use a method for extending your growing season you may be able to harvest vegetables well into December and winter. (Check out my March 2, 2011, article “Extending Your Growing Season With Mini Greenhouses“).

Some of these cool season plants will continue to survive even in the harshest winters. I left my leeks, onions, shallots, beets, and parsnips in the ground through the winter. They all came back and began greening again when the spring warmth returned. The leeks and parsnips that had a winter to rest were twice the size of ones harvested before the ground froze hard.

Thick mulch helped these leeks and shallots overwinter

If you’re interested in a second fall crop but don’t want extra effort, just let your spring crops go to seed. My spinach, arugala, radish, and lettuce plants flowered, went to seed, browned, and faded. I collected some of the seeds and pulled the plants. Many of the seeds that scattered on the ground have sprouted and are ready to give me a second harvest. It helped that I amended and turned over the soil in those spots for the beets and broccoli, and I’m willing to let the volunteers share the same bed.

Some of the lettuce volunteers missed the bed

Whether planned or by accident, take advantage of the growth characteristics of cool season plants and enjoy a second season. Grow a fall crop.

How to Thin Plants

Thinning plants in your vegetable garden can lead to bigger, better harvests. When plants are crowded with others they compete for water, sun, and nutrients and tend to be stunted and unproductive. When plants have plenty of room to grow they’re more likely to perform well. Thinning plants also provides improved air circulation, helping reduce the likelihood of fungal diseases. Gardeners can give their plants the best chance for success by removing competition; this is thinning out the garden bed.

Thinning should not be confused with pruning. Pruning is the practice of removing branches and parts of a specific plant, thinning is removing the entire plant.

Carrot seedlings often need thinning

When you thin plants choose an appropriate method of removal. Small seedlings can be pulled from the ground. But be cognizant of nearby plants. If you yank one plant you may disturb the roots of its neighbor and effectively destroy both plants.

If plants are close together and you suspect pulling one of them will affect another, cut the plant to be thinned. Pruning shears or small scissors work well to cut the stem close to the ground. Cucumbers, beans, peas, squash, and melons have tender roots and are best thinned by cutting if the plants are anywhere near each other.

Thinning out a crowding cucumber

Plants that sit alone can be dug up with a trowel or shovel. Digging up a plant may provide the opportunity to transplant it to another location. I’ll often thin out my flower beds and transplant the thinned seedlings to another part of the bed or pot them to be given away.

Thick groupings of plants like lettuce, spinach, and other greens can be thinned with a rake. When the plants are about an inch tall lightly drag a rake across the soil surface. The tines will remove some of the small plants while leaving others spaced apart.

When determining how to thin and how much space to provide, think about the final size of the plant.

Seed packets often provide guidance for thinning. A carrot seed packet says to thin to 1 to 3 inches; carrots are narrow and don’t spread so you only need enough space for the big root to grow. An onion seed packet says to thin to 2 to 5 inches; onions grow bigger than carrots and need more room between them. Lettuce may need 8 or 10 inches, or more, depending on the size of the mature head.

Big, vining plants like squash take up a lot of garden space and thinning them enables the gardener to direct the growth. Thinning also controls the future harvest. I planted six zucchini seeds but I only want two plants; six plants would produce more zucchini than I could ever use while two is very manageable. The strongest, best-spaced plants remain.

Too many squash plants

Plants can be thinned at any stage of their life cycle, but it’s most beneficial to do it when they’re young. After the second set of true leaves emerges, seedlings are usually strong enough to survive. That’s a good time to decide which ones stay and which ones go. Thinning small plants before they stunt the growth of a neighbor is better than waiting until after they become a problem.

You can delay thinning edible plants like lettuce, spinach, and beets until the leaves are big enough for a salad. Thin these out to give room for the remaining plants and then use them in the kitchen. Root crops like carrots, radishes, and turnips will be quite tasty when small; thin out these plants periodically at different sizes and eat them too.

I often conduct two phases of thinning. I’ll remove seedlings before they stunt the growth of their neighbors and then wait a few weeks for the plants to get healthy and strong. Then I thin a second time to choose the strongest plants with the best spacing for the bed. This works particularly well for plants like squash and cucumbers when I want the biggest and healthiest plants headed into my short growing season.

The same squash, after initial thinning, will be thinned again

It’s best to thin in the early evening with the soil damp. Damp soil allows small plants to be pulled easily and the absence of harsh sun allows the remaining plants to get used to their new conditions before immediate exposure to heat and light. Watering well after thinning a bed also gives the remaining plants an extra boost along with their newfound spacing.

It’s possible to plant a garden and never thin out anything. Sowing seeds and placing transplants with perfect spacing between them means you don’t need to remove overcrowded plantings. This can work well for big seeds like pumpkins and plants like tomatoes and peppers. I place them in my garden where I want them and wait for the harvest. I sow my beans and peas in a perfectly spaced grid that allows them to grow up a trellis; their seeds are big and easy to place. Blocks of corn are planted with ideal spacing too.

Many other seeds like carrots, lettuce, onions, and spinach are sown randomly in rows and then thinned out after the plants emerge. The seeds are too small to place with exact measurement and it’s easier to wait to thin after germination reveals which small plants need to be removed. Other seeds like beets are easy to place but multiple plants will emerge from a single seed and then need to be thinned.

Plants with bigger seeds like cucumbers, melons, and squash are often sown closer together than the final plants will be. Varying rates of germination, insect damage, and uneven sowing means some plants will start off better than others. It’s common to plant six of these kind of seeds in a mound, get four or five that grow, and then reduce them to two or three plants. This allows you to choose the biggest and best plants for that garden area.

This year I planted many, many pickling cucumber seeds in a raised bed. I’ve had problems in the past with low germination rates, sun and hail damage, and insects eating seedlings. Extra attention by me, and gentle, warm weather resulted in more than 80 plants emerging. That’s many more than that bed can support so about 75 percent need to be thinned out. The remaining 20 plants should provide plenty of cucumbers. Because they won’t have to compete for water, sun, and nutrients, those 20 plants will produce more fruit than 80 overcrowded plants in the same space.

Too many cucumbers for one bed

All of those seeds came from the same packet. Seed packets may provide dozens of seeds when you only need a handful of plants. Because seeds are only viable for one or two seasons it makes sense to plant many of them and select the ones you want after the plants begin to grow.

Emotionally, it can be difficult to thin out healthy plants. Most of us work hard to get our plants to grow and then we have to intentionally undo our labor. That’s one reason I transplant the thinned out plants when I can. For those who are hesitant to thin, try an experiment. Thin half of a bed and let the other half grow as sown. At harvest or the end of the season, compare the two sections. Chances are the thinned half will be healthier and more productive.

When the thinned out plants find a place in the kitchen or compost pile you can gather solace by knowing that they served a purpose in the garden.

Like weeding, thinning is a necessary activity to keep garden plants healthy and productive. When done properly the beneficial results will be obvious.

The Best Way to Grow Tomatoes

Tomatoes can be found in most American vegetable gardens. For many gardeners, growing tomatoes consists of little more than buying a plant from a big box garden center and placing it in a hole in the ground. There are many other options and for you there may be a better way — actually, six different ways to plant tomatoes.

Let’s begin with a bale of straw as the planting spot. That’s right… straw. I had good success by placing a tomato plant in a hole bored into the middle of a straw bale. Begin by soaking the straw a few days before you plan to plant. This softens the straw making it easier to dig a hole; it also begins decomposition within the bale. Use a trowel to scoop out a hole 12 to 18 inches deep (30-45 cm) and fill it with compost. A standard straw bale can easily hold two or three tomato plants.

Plant in straw

Any time you plant tomatoes you should bury as much of the plant as you can to help encourage a vigorous root system (see my May 24, 2011, article “How to Plant Tomatoes“). By placing your plants deep into the holes in the moist straw bale you give the tomato roots plenty of space to expand. The straw retains moisture well and requires watering less often than other garden beds. The compost and decomposing straw provide some nutrients but you should plan to fertilize regularly.

The easiest and simplest way to plant tomatoes is in a bag of potting soil. The bag is the garden bed. Make slits in the top of the plastic potting soil bag and insert the end of your hose. Soak the potting soil well; you want it thoroughly moist. I recommend punching holes or making small slits in the bottom of the bag for drainage. Place the bag flat on the ground and wait a few days for excess water to drain, then plant your tomato horizontally through the top slit.

Tomato in a bag

You can use this method in any spot that’s just a few feet square, in between raised beds, at the end of paths, or in garden corners. The bag is very effective at retaining moisture so this method also requires less watering. However, it is a little more difficult because you have to apply water and fertilizer through the slit; it won’t catch any rain or sprinkler water.

Another flexible variation is to grow tomatoes in pots. This is a great option for gardeners without a garden spot that gets full sun or who have limited space. Big root systems make big tomatoes so use at least a 14-inch pot filled with potting soil; bigger is better. Pots tend to dry out faster than normal garden beds so these tomatoes will probably need watering every day. As the plants grow a small trellis or support will help keep the vines from sprawling everywhere.

Plant in a pot

Tomatoes in pots work well for apartment dwellers. My daughter had good results with a single pot on her balcony. Pots can be moved to take advantage of sunny spots and can be brought indoors if cold weather threatens, extending the growing season. They can also be grown just outside the kitchen door making harvesting fast and easy.

Growing tomatoes upside down is another option that has found a following in recent years. Shiny advertisements and catchy names for upside down containers make the concept appealing. Anywhere you can hang a bag becomes a potential tomato garden. Growing tomatoes this way gives you the opportunity to fill the growing bag with good potting soil and deliver water and fertilizers straight to the roots.

Upside down tomatoes

You don’t need to water as often with this method, but the structure supporting the hanging bag needs to be sturdy enough to handle the weight of soil, a big plant, and ripe tomatoes. Some manufacturers offer movable supports that can be used on a deck or patio.

A raised bed is an ideal way to grow tomatoes. Raised beds heat up sooner than open ground so tomatoes can be planted earlier than standard rows. The soil is often better and has fewer compaction issues. When mulched, watering requirements drop. Weeding and harvesting is easy because of easy access. More plants can often be grown in a smaller space.

I find that trellises work well in a raised bed because the bed structure helps support them; last year I used welded metal panels bent into an arch. It supported plastic sheets to warm the plants early on and supported the plants as they grew large.

Plants under the trellis

The most common way gardeners grow tomatoes is in rows in open beds. This method has worked well for many gardeners for a very long time and is a good way to grow if you have the space. To be most effective the entire bed should have amended soil and have a good irrigation method. Tomato plants can grow large and a trellis system is almost always needed; open bed growing limits the trellis options.

I’ve used all six methods with varied results.

Last year big tomatoes came from the straw bale. The plants did very well but as they grew large I was concerned that their weight would topple the bale or that they would sprawl too much; a trellis system was difficult to set up. Regretfully deer damaged the plants before they caused a problem.

The first tomato of the season came from the potting soil bag. That plant also had the biggest root ball. The plant did well but the specialized watering requirements added time to the process. I also found that my feet and garden hose had a tendency of snagging on the bag because it was too close to my garden path.

Claims for bumper crops abound, but I’ve grown upside down tomatoes with mostly negative results (see my May 6, 2011, article “Upside Down Tomatoes“). The plants were stunted and not nearly as large as with the other methods.

Tomatoes in pots do well with extra attention. It’s nice being able to bring the pots inside when a frost threatens and the other plants are injured; however, bigger pots are harder to move. As long as the soil doesn’t dry out this method works very well.

My favorite way to grow tomatoes is in a raised bed. I can keep my plants contained in a designated area, mulch and water as needed, and keep basic chores like weeding to a minimum. The biggest tomato plants in my garden, by a large margin, were in raised beds.

Best success in raised beds

Open row plantings work well but the space is often better used by other sprawling plants like melons or squash. For harvest, you need paths between plants and this takes up more space. Any one of the other methods of growing tomatoes is more efficient for limited garden plots.

Another option for some gardeners is hydroponic gardening. Tomatoes can be grown in water only, but this method requires specialized equipment and procedures and isn’t suitable for most home gardeners.

Experimenting with new options is fun and informational. I plan to repeat the straw bale and pot plantings, but will probably bypass the potting soil bag. Upside down tomatoes are probably gone from my garden for good. My focus will be on growing tomatoes in raised beds. I wouldn’t know about how all of these methods worked for me if I hadn’t tried them.

Regardless of which method you use, tomatoes should probably find a place in your garden. If you have a successful method continue it, but think about trying something new. Have fun.