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Growing Healthy Tomatoes: Home

Photo by Ivo M. Vermeulen
Photo by Ivo M. Vermeulen

Growing Healthy Tomatoes

Growing healthy tomatoes is easy as long as you get off to a good start. Tomatoes love soil that is rich in organic matter and has good drainage. Add compost and aged cow manure into the vegetable garden every season (either in fall or spring). Full sun (about 6 hours) is also important for healthy plants.

Once these requirements are met, you are ready to begin. You can either pick up transplants at your local garden center or farmers market or sow your own seeds. If you buy your plants, choose tomatoes that are being grown in individual pots rather than in small six-packs; a healthy root system equals a healthy plant.

When growing your own, start the seeds 6 to 8 weeks before the last frost date. Sow 1/4 inch deep in flats or pots and keep the soil moist. Bottom heat from a propagation mat or the top of your refrigerator will improve germination. Thin out seedlings and remember to harden off for a week before you move them outside. Transplant your tomatoes into the garden after the soil has warmed up, usually May 15 in the New York area.

Tomatoes will root from their stem, so plant them deeply. Dig a hole slightly deeper than the pot size, strip off the lower leaves, and plant so that the bottom portion of the stem is underground. Alternatively, you can dig a small trench and gently lay the root ball and lower half of the stem horizontally so that only the top of the plant rests above the soil. Space your tomatoes 18 to 36 inches apart depending on the ultimate size of the plants.

Be creative when staking your tomatoes. Catalog companies sell tomato ladders, tomato spirals and tomato cages in all shapes and sizes. Rambling cherry tomatoes often grow over a trellis. Experiment with A-frames and other interesting structures. Attach your plants to the structures with soft twist ties, twine (in a figure eight configuration) or Velcro plant ties.

Pruning requirements depend on the type of tomato plant: 'determinate' or 'indeterminate'. Determinate tomatoes are fairly compact plants requiring minimal staking and very little pruning. They mature to a determined size (generally 4 ft.) and their fruits mature in a relatively short time (approximately 6 weeks). Determinate and dwarf tomatoes are ideal for growing in containers (10 to 15 gallons is a good size). Indeterminate tomatoes, on the other hand, grow as big as you let them--as high as 8 to 10 ft. tall--and continually produce fruit as long as the weather cooperates. These vigorous growing plants benefit from pruning.

Pinch out the suckers or side shoots (the small growth that appears in the V-shaped area where the stems attach).  While it is important to keep a decent amount of foliage on the plants for energy and to prevent the tomatoes from getting scorched by the sun, many indeterminate tomatoes are so vigorous that if you don't do some pinching you will end up with a jumble of foliage. Pinching makes staking easier and will concentrate the plant's energy, making a more manageable plant.

Water tomatoes deeply at least once a week if there is no rainfall; consistent watering is important for healthy fruit. Timing is also important; water early in the day so that you will not encourage any fungal or bacterial diseases. Mulch keeps the weeds down, maintains even moisture and aids in the prevention of pest and disease problems. Salt marsh hay substitute is an effective mulch for tomato plants.

Fertilize your tomatoes just two times during the season--two weeks after planting and again just when the fruits are starting to set. Use an organic fertilizer with low numbers or a fish or seaweed emulsion. Adding organic matter into your soil in fall or early spring provides the most lasting benefit to your garden.

When Trouble Appears: Pests and Diseases

One problem that often arises in the garden is the presence of cutworms. They come out at night and chew through the base of tomatoes. The easiest way to control this pest is to put a homemade collar around the young seedlings to protect them. A piece of glossy magazine paper wrapped several times around the base of the plant can serve as a collar. Alternatively, simply standing a toothpick on one side of the plant stem can also deter cutworms from severing the stem.

Tomato hornworms will chew their way through tomatoes and easily defoliate a plant. These little pests have a distinctive green and white striped body with black horns on their ends. They are easy to spot and they should be picked off by hand and thrown into soapy water.

Blossom end rot is a common and manageable problem in tomatoes. If the bottoms of your fruits have brown or water-soaked patches, then your plant suffers from inconsistent watering or drought stress, is getting too much nitrogen or is not getting enough calcium. To rectify the problem, wait until the soil has warmed sufficiently in spring to plant your tomatoes, mulch your plants, water consistently (approx. 1 inch per week--a good soaking) and avoid high-nitrogen fertilizers. If a calcium deficiency is the problem, add lime with seaweed extract to your soil to boost calcium levels. Good cultural care is the best prevention.

Cracking is also a symptom of irregular watering. Cracking tends to happen with heavy rainfall and over-watering.

Foliar diseases can be devastating in tomatoes. Verticillium wilt can be a problem in zones 4 to 6, while Fusarium wilt tends to be a problem in the South. Both are fungal diseases that cause tomatoes to wilt and the foliage to yellow and die. Never dispose of any disease-ridden plant in your compost.

More common are early blight and late blight. These diseases generally form spots that start on the bottom foliage and move up. Late blight moves quickly and will rapidly destroy the plant. Early blight can sometimes be contained by pulling off infected leaves. It is important with all foliar diseases to mulch carefully, properly space and stake your plants for good air circulation, and water early in the day so that moisture will not remain on the foliage. Crop rotation is paramount in these situations, as the fungal spores will over-winter in the soil. Rotate crops on a three-year plan and do not plant potatoes, peppers or eggplants (all in the Solanaceae family) in the same location. Finally, choose from a large selection of disease-resistant cultivars that are currently available.


Tomatoes originated in the Andes Mountains of Peru, where eight different species of tomatoes still grow in the wild. They were first brought to Central America and domesticated by the Aztecs, who grew a yellow form of the cherry tomato (Lycopersicon esculentum var. cerasiforme), which they mixed with peppers and salt to create the first salsas.

They named these little fruits xitomatl, which means "plump thing with a navel." Subsequent Central American tribes renamed them tomati, and they were brought to Europe by Spanish and Italian explorers ranging from Hernando Cortez to Christopher Columbus.

When the tomato first arrived in Europe, it was viewed with suspicion. Tomatoes are members of the nightshade family (Solanaceae), and their foliage is similar to deadly nightshade (Atropa belladonna), a well-known poisonous plant that was used as a hallucinogenic drug and beauty aid. It was fashionable in medieval courts for women to dilate their pupils with drops of belladonna. When taken as a hallucinogen, the drug induced visions and a feeling of flying associated with the practice of witchcraft.

To make matters worse, the upper class ate on pewter plates that contained a high lead content. High in acid, tomatoes would cause the lead to leach out, resulting in poisoning. The first tomatoes, named pomi d'oro (golden apples) by the Italians, were thought to be inedible; they were viewed as ornamental plants. Only the lower class who ate on wooden plates consumed the fruits.

By the 18th century the tomato had finally cast off its bad reputation, although its original botanical name, Lycopersicon esculentum, encapsulates its dubious history. Lycopersicon means "wolf peach," which hearkens back to its association with witchcraft, werewolves and poison, while esculentum means "edible." Today, like so many plants, the botanical name has changed and it is now know as Solanum lycopersicum.

Some tomatoes, particularly heirloom varieties, have colorful histories. One favorite is the story of Charles Byles, a radiator repairman who, during the Great Depression, turned his attention to hybridizing tomatoes. His goal was to hybridize a tomato that could feed a family of six. A novice grower, "Radiator Charlie" crossed four of the largest tomatoes that he could find to breed a monster tomato.

By the 1940s, Charlie was selling seedlings of his new tomato for $1. People were driving up to 200 miles to buy his tomato that produced 2 1/2 to 4-pound, tasty, pinkish-red fruits all summer. Within several years, Charlie was able to pay off the mortgage on his home, hence the name of his hefty heirloom, 'Mortgage Lifter.' Sometimes the name of the heirlooms reveals either the grower or hybridizer such as 'Livingston's Perfection' or 'Aunt Ruby's Green German'; it often alludes to its site of origin such as 'Amish Paste', "Arkansas Traveler' or 'Hillbilly' (West Virginia).

Types of Tomatoes

Tomatoes can often be hybrids (F1 hybrids) or open-pollinated. Hybrids were created to produce a higher yield and better uniformity (e.g. nice, perfectly-shaped, round fruit). However, if you save the seeds and try to grow them the following year, you will not get the same tomato. These hybrids (crosses) are not stable.

Open-pollinated tomatoes are generally self-pollinating tomatoes that will come true to seed. One advantage of these tomatoes is that they have been grown in specific regions and have adapted to their local climates. Heirlooms fall into this category and are known for an incredible variety of color, shape and delicious flavor.

There are many types of tomatoes to choose from, and they all have distinctive features, such as cherry tomatoes that are sweet as candy, minuscule currant tomatoes, paste tomatoes that are wonderful for cooking and sun-drying, medium-sized tomatoes perfect for salads, and beefsteak tomatoes ideal for BLTs.

The list of heirloom types gets even longer when you realize there are peach tomatoes with a fuzzy coating, bell pepper tomatoes with a hollow cavity for stuffing, oxheart tomatoes with a tapered base and ribbed tomatoes that are a work of art.



or Indeterminate

Hybrid or

'Amish Paste' ind. open paste
'Better Boy' ind. hybrid large
'Brandywine' ind. open large
'Celebrity' det. hybrid medium
'Cherokee purple' ind. open large
'Early Girl' ind. hybrid medium
'Gourmet Yellow Stuffer' ind. open stuffing
'Green Zebra' ind. open medium
'Nyagous' ind. open medium
'Oregon Spring' det. open medium
'San Marzano' ind. open paste 
'Stupice' ind. open small 
'Sun Gold' ind. hybrid cherry
'Sweet Millions'  ind. hybrid cherry
'Tangella' ind. open medium
'Tiny Tim' det. open dwarf
'Wapsipinicon Peach' ind. open medium
'Zapotec' ind. open large, ribbed

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