Posted by Brent Wilson on 9/19/2016 to Vegetable Gardening
When it comes to growing tomatoes in the vegetable garden, nothing is more important than soil. The soil is where tomato plants will get the nutrients they need to thrive and produce good fruit. Most tomatoes take 100-days to bear fruit, so follow these easy directions and get ready to harvest the fruits of your labors and enjoy that first BLT of the season.
Determinate or Indeterminate?
Tomato plants generally fall into two categories: determinate and indeterminate. Determinate (bush) tomato plants are bred to stop growing usually somewhere around 3'-4' feet tall. When flowers blossom at the tips of the branches, the plant has reached its full height. The fruit of a determinate tomato plant ripens all at once. Because of this trait, this type of tomato plant is useful for those who want to grow tomatoes for canning. Since many determinate plants stay on the short side, they can also be ideal for the small-space gardener.
Indeterminate tomatoes continue to grow much taller to 6' or more in height, depending on the variety. This type continues to produce tomatoes all growing season until a hard frost hits and stops them in their tracks. These plants are particularly desirable if you'd like a continuous harvest for slicing or salad tomatoes.
Good Soil is Important!
If you want to produce top-notch tomatoes, you'll need to grow the plants in deep, loamy, and well-drained soil. Constantly soggy or wet soil is not tolerated. One way to accomplish this for them is to build "raised", or "mounded" garden beds
Few gardeners are lucky enough to have ideal soil for growing tomatoes. Overly sandy soil might not hold enough water and nutrients. Heavy clay soils are often too compact and lack good drainage. But, in most cases and with a little work, you can easily turn the average to poor soil you have into a good tomato growing medium by amending the soil with organic matter.
The key to good garden soil is organic matter. When starting a new garden, mix in a 2 to 4 inch layer of organic matter/compost into the soil, such as mushroom compost, composted manures, or your own homemade compost. Thereafter, between each season, till or turn in a 1/2-inch layer or so of compost into the garden soil.
Tomato plants grow best in a mildly acid to neutral soil that ranges from 6.2 to 6.8 on the pH scale. Many average garden soils fall between a pH range of 6.0 to 7.0, but it's still a good idea to test the soil.
Testing Soil pH Soil pH is a measurement of the alkalinity or acidity of soil and is measured on a scale of 1-14, with 7 as the neutral mark. Any measurement below 7 indicates acid soil conditions, and anything above 7 indicates alkaline. If you're unsure about the pH of your soil, or whether or not it is suitable for growing tomatoes, it's a good idea to test the pH in the planting area. You can quickly test soil pH with an inexpensive soil pH tester probe. To raise the pH (make more alkaline) you can add pelletized limestone to the soil. To lower the pH (make more acid) you can apply Soil Sulfur, Aluminum Sulfate, or Chelated Iron. Adding organic compost to the soil or using compost as mulch can also help to increase acidity and maintain acid soil conditions.
Learn More: What is Soil pH and How To Adjust It?
Good Soil Drainage is a Must!
You can always supply extra water when needed, but you cant take it away. As previously mentioned, to have success with growing healthy, productive tomato plants good soil drainage is essential. Tomato plants cannot tolerate a constantly soggy or wet soil.
How To Test Soil Drainage If you are uncertain about soil drainage in the area you intend to plant your vegetable garden, it's well worth taking the time to test the drainage before planting. To test soil drainage, dig a hole 12" wide by 12" deep in the planting area. Fill the hole with water and let it drain. Then, after it drains, fill it with water again, but this time clock how long it takes to drain. In well-drained soil the water level will go down at a rate of about 1 inch an hour. A faster rate, such as in loose, sandy soil, may signal potentially dry site conditions. A slower rate indicates poor draining soil and could be a caution you might need to improve drainage, plant in a raised mound or bed, or look for plants that are more tolerant of wet or boggy conditions.
To ensure good soil drainage, I highly recommend planting in raised garden beds or raised/mounded rows, which raise plant roots above the water table. Raised rows should be mounded 5 to 10 inches in height.
Soil Amendments Help
Tomato plants can benefit tremendously from the incorporation of organic compost in the soil. Adding decomposed organic compost will improve any soil structure. You can purchase or make your own compost. Mushroom compost and composted cow manure are two of many soil amendments available at your local nursery and garden center. Once you have cultivated your garden area and prepared the soil, it is ready for the plantings.
Sun is Necessary!
Tomatoes grow and produce best in full to mostly sun. Therefore, choose an area to grow your tomato plants that receives a minimum of 6 hours of full sun per day. The more sun, the better.
Tomato Planting Instructions
Inspection of Tomato Plants
First, inspect all of the transplants before planting them in the garden. Look for insects, wilting or blight. Plant only healthy plants.
For your plants to produce large healthy tomatoes, give them plenty of room to grow. I like my plants to get as much sun as possible so space them 3 to 4 feet apart in the row. If you'll have more than one row, space rows at least 4 feet apart. The more you space them, they better they can breath. Good air circulation can help to cut down leaf disease as more sunshine will reach more leaves. Another benefit of spacing further apart is that or provides easier access for harvesting from all the way around the plant.
When planting a tomato plant, cover the stem up to the plant's lowest leaves. You can even cover the first few leaves with soil. Roots will grow along the buried stem to make the plant stronger. You can plant so that a full 2/3 of the plant is underground. Some folks, like me, dig a trench about 2 to 3 inches deep and lay the plant horizontally in the trench, as shown in the picture. This way the roots are closer to the surface where soil temperatures are warmer.
After planting, it's a good idea to spread some mulch around the base of your plants. I apply a 4" layer of wheat straw or some other weed-free straw around the the plant, 18 inches or so out from the stem. This is an effective way to prevent weeds, preserve water, keep the soil warm and have a barrier between the lower leaves of the tomato plant and the garden soil. Leaves of tomato plants should never be allowed to touch the ground as soil-born diseases can be spread.
If you will be using a wooden stake, drive an eight foot stake at least 2 or 3 feet in the ground (the deeper, the better to provide good support). If you will be using a tomato cage, wait until after planting for set up. Use a soft material to tie vines to stake or support structure.
Care of Tomato Plants
Feeding Tomato Plants
To produce the best fruit possible, your tomato plants will need to be fertilized regularly. If you're like me, and want to grow organically, you can use an organic plant food. Read and follow instructions on the product label.
Watering Tomato Plants
Watering tomato plants is as crucial as pruning, preparing soil, feeding, etc.. If neglected or done incorrectly it can lead to development of fungus and other disease that could cause your tomato plants to underperform or even die. It's easy to make mistakes because the methods we use will vary with weather conditions, where we grow our tomato plants and what type of garden we are growing them in.
Tomatoes love the moisture, but at the same time, they can't stand being drenched to a point where their roots are consistently standing in water. Avoid pouring too much water as it makes air exchange in the roots and soil more difficult. So, how much water is too much?
The amount of water your tomato plants will need will depend on several factors:
1. Are you gardening in a hot and dry environment, or one that receives plenty or average rainfall? In drier conditions you will need to monitor watering of your tomato plants more closely, making sure not to allow the soil to totally dry out. In climates or conditions where there is more than average rainfall, overwatering can be a problem. You will need to plant your tomato plants in "raised beds" or "raised rows" to provide proper drainage. Then, during dry periods you can check the soil moisture with your finger to determine if plants need water.
2. Are you growing your tomato plants in clay-based, loamy, or sandy soil? Plants grown in clay-based garden soil will usually require less supplemental water. Clay doesn't drain as quickly as sandy soils so you must be careful not to overwater your plants. If you are growing your tomato plants in containers that are filled with loamy potting mix or soil, always use the finger test to check for moisture before watering. Also make sure you choose pots that have drainage holes at the base. Because it drains so quickly, sandy soil may need to be amended with peat moss to help retain moisture. Whichever type of soil you are growing your plants in, just make sure not to over or under water them. The finger test method is always the best way to check if a plant needs to be watered.
3. If you are growing your tomato plants in raised beds with well-amended soil, keep in mind that the soil will drain quicker than in garden beds planted at ground level. This means your plants will be less susceptible to too much moisture in the soil, but you'll need to keep a closer eye on your plants to make sure they are receiving ample water.
Watering your tomato plants one at a time by hand is recommended over using automated irrigation systems. Sometimes, soil porosity can be different from one plant in the garden to another. Each of your plants is a unique individual so watering them individually is the best way to go.
Always water around the base of the plant, avoiding the foliage. Do not over water or soak seedlings as this can promote disease and rot. Water early in the day to discourage blight.
Pruning Tomato Plants
Yes, that's right...your tomato plants can benefit tremendously from a little pruning here and there. But it's a little easier said than done so I wrote an article about it: How To Prune a Tomato Plant
You can always remove bugs by picking them off. What you do with them after that is up to you. But here's a few other tips on insect control...
One of the best things you can do to ward off the bad bugs involves companion planting, which means planting plants side by side that get along or benefit each other in one way or another. There are several plants that are good companions for tomatoes and will help to ward of insects. One also actually improves the flavor. That plant is basil. Not sure how it does this, but it does. It probably has something to do with keeping the tomato plant healthy. The aroma of basil deters many tomato pests so that the plant can concentrate on flowering and fruit production. So, plant a basil beside each tomato plant or between two tomato plants!
Tomato plants prefer to be planted by chives, parsley, marigolds, nasturtiums, garlic bulbs, and carrots.
There are many chemical products available on the market for controlling insects in the vegetable garden. However, there's a very simple recipe you can make from safer products that can always be found in your kitchen. Here's the recipe:
In a jar, combine 1 teaspoon dishwashing liquid and 1 cup vegetable oil. Shake vigorously. In an empty spray bottle, combine 2 teaspoons of this mixture and 1 cup water. Use at 10-day intervals (or more often if needed) to rid plants of white flies, mites, aphids, scales, and other pests. See, that's easy, less expensive, and safe!
Tomatoes are susceptible to cutworms, but placing a 3-4 inch nail next to each stem before planting, or wrapping strips of newspaper around the bottom of the stems, will help prevent these pests. A paper cup surrounding the base of the stem also works well.
Tomato plants are susceptible to several diseases, many of which can prevented by taking a few simple measures. A good example is early blight of tomato, pictured below. Early blight is generally one of the most severe tomato problems faced by home vegetable gardeners. This fungus disease is correctly named since it gets off to an early start following spring rains.
Early blight tends to be more severe when periods of rainy weather are experienced after transplants are set. Plants are more likely to become infected by the blight fungus under these conditions.
Early blight first shows up as a leaf blight on the lower part of plants. The disease moves upward, and by early to mid-summer, early blight has caused a "firing-up" of foliage over most of the plant.
As the disease progresses, leaves turn yellow, wither, and drop from plants. Tomato plants severely infected by early blight produce low yields of undersized fruit. Generally, fruit also show signs of sun-scald since leaves aren't present to protect fruit from direct sunlight.
Early blight overwinters on infected plant tissue and is spread by splashing rain, irrigation, insects and garden tools. The disease is also carried on tomato seeds and in potato tubers. In spite of its name, early blight can occur any time throughout the growing season. High temperatures (80-85 degrees F) and wet, humid conditions promote its rapid spread. In many cases, poorly nourished or stressed plants are attacked.
For top yields of high quality fruit, early blight control is essential. Early blight-resistant tomato varieties aren't available, so gardeners have to use a combination of disease management practices.
Prevention and Treatment of Early Blight:
- Properly space and prune or stake plants to improve air circulation.
- If you prune away affected leaves, make sure to disinfect your pruning shears (one part bleach to 4 parts water) after each cut.
- Keep the soil under plants clean and free of garden debris. Add a layer of organic compost or mulch to prevent the spores from splashing back up onto vegetation.
- Use drip irrigation and soaker hoses to help keep the foliage dry.
- If symptoms of early blight are present, begin applying a copper based fungicide weekly until harvest.
- Remove and destroy all garden debris after harvest and practice crop rotation the following year.
- Do not add infected plant parts to your compost pile.
Control and Prevention of other Tomato Diseases:
- Plant disease-resistant tomato varieties.
- Avoid overhead irrigation with sprinklers. Use surface watering methods such as drip-irrigation or hand watering from a garden hose. Do not handle plants when the vines are wet.
- Control weeds in and around the garden plots. Weeds not only compete with vegetables for soil moisture and nutrients but also serve as hosts for insects and disease organisms.
- Control insect pests (especially aphids) which may transmit a disease organism from plant to plant.
- Remove abnormal appearing plants as soon as they are observed. Virus diseases may be involved. To reduce the spread of viruses, wash hands and tools with a detergent after handling diseased or unusual looking plants.
- Do not use tobacco products while handling tomato plants. These products may carry viruses, especially tobacco mosaic virus.
- Spray tomato plants with a calcium solution made for blossom-end rot.
- If possible, choose a sunny location for your tomatoes (at least 6 hours of sun). You are less likely to have leaf disease problems in a sunny location than in a semi-shady one.
Here's some sprays you can make yourself to help control and/or prevent common diseases on tomato plants.
Baking soda contains sodium bicarbonate, which has antifungal properties that can help naturally control early tomato blight, powdery mildew and anthracnose. Mix 1 tablespoon of baking soda mixed with 2 1/2 tablespoons of vegetable oil. After throughly mixing, add 1 gallon of water and 1/2 teaspoon of castile soap. For easier application, transfer the mixture to a pump sprayer and thoroughly apply the spray to the plants, ensuring the mixture covers both the upper and lower leaves as well as the soil. Multiple applications every 5 to 7 days may be needed in order to control the fungal disease. This spray can be used as a preventive measure or to control the fungus at the first signs of infection.
Aspirin Fungal Spray
Aspirin helps to treat powdery mildew, evidenced by a white powdery substance on leaves. Use uncoated aspirin tablets measuring 325 milligrams and dissolve two tablets in 1 quart of water. Spray the tomato plants thoroughly to coat the entire plant, including the undersides of the leaves. If after a week powdery mildew symptoms persist, reapply the aspirin treatment to the tomatoes.
Tomato Virus Prevention Spray
The tomato virus protective spray prevents several viruses from attacking tomato plants, including tomato leaf blight, tomato mosaic virus and spotted wilt virus. The recipe is 1 gallon of water, 8 ounces of skim milk and 1/2 teaspoon of antitranspirant. Skim milk adds calcium, which is a common deficiency in tomato plants, and antitranspirant will protect the surface of the tomato plant from disease spores without interfering with the plant’s pores. When spraying the plant with the mixture, ensure you cover all areas of the tomato plant, including the undersides of the leaves.
How To Prevent Tomatoes From Cracking
Splitting or cracking of tomatoes growing on the plant is quite common and is often caused by fluctuations in soil moisture. This can be caused when watering too heavy after a long period of not watering. It can also be caused naturally when there is a period of dry weather followed by a period of heavy or above average rainfall. Splitting and cracking usually occurs in the later stages of fruit development, just when the fruit starts to ripen.
The best way to prevent tomatoes from splitting or cracking is to practice a watering method and schedule. It's best to water tomato plants deeply on a regular basis than to provide only sporadic, light waterings. That being said, be careful not to overwater tomato plants. They like a moist but well-drained soil however constantly wet or soggy soil will most likely cause harmful disease.
Adjust the amount of watering you do to the amount of rainfall received. A good natural soaking rain usually lasts longer than a hose watering with treated water, unless you are watering with natural water from a well which would be equivalent to a natural rain. When "determinate" tomatoes start to ripen you can greatly reduce the amount of watering to reduce the chances of cracking. Determinate tomatoes are ones that produce heavily all at once - at a "determined time." Indeterminate tomatoes produce tomatoes freely throughout the season.
Another thing that can cause tomatoes to crack is over feeding when they are starting to ripen. I use a slow-release, mild organic tomato food to fertilize tomato plants. When fruit starts to ripen I usually discontinue feeding, especially on determinate varieties.
Also, there are some tomato varieties that are "crack resistant." You could look for and plant these varieties. But, still, follow regular watering practices and avoid over feeding.
Pick tomatoes early and allow them to ripen indoors. If you pick tomatoes right when you see their skin start to crack, they are still okay to eat. If the tomatoes are left on the plant and the cracks are severe, to be safe rather than sorry, I would suggest not eating these. Instead, remove them from the plant and discard to avoid attracting insects and onset and spread of disease.
Practice crop rotation in your vegetable gardening by planting tomatoes and other vegetables in a different spot every year. Avoid planting tomatoes beside potatoes or members of the cabbage family.
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