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Updated: Jul 1

Botanical name: Solanum LycopersicumPlant type: vegetableSun exposure: Full sunSoil PH: Acidic slightly acidic to neutralBloom time: summer

Growing Tomatoes from Planting to Harvest

Tomato plants are tender “warm-season” crops and can not bear frost. It’s important not to put plants in the ground too early. Tomatoes are sun worshipers. Tomatoes take 60 days to more than 100 days to harvest, depending on the variety. Due to their relatively long growing season requirements (and late planting date), most gardeners plant small “starter plants” or transplants instead of seeds.Choose young tomato plants from a reputable nursery. Good starter plants are short and stocky with dark green color and straight, sturdy stems about the size of a pencil or thicker. They should not have yellowing leaves, spots, or stress damage nor have flowers or fruits already in progress.

Types of Tomatoes:Determinate tomatoes, Determinate tomatoes, better known as “bush” varieties grow 2 to 3 feet tall. These varieties tend to provide numerous ripe tomatoes at one time, do not put on much leaf growth after setting fruit, and tend to fruit for a (relatively) brief period of time. They are generally productive earlier than the vining varieties, and not in the latter part of the growing season. Determinate tomatoes do not require staking or caging. These plants are ideal for containers and small spaces. Most paste tomatoes are determined (which works well for making sauce and canning).Indeterminate tomatoes, better known as “vining” varieties produce the largest types of mid-to late-season slicing tomatoes all summer and until the first frost. Because indeterminates experience more leaf growth, their production tends to be spread more evenly throughout the season. Indeterminate tomatoes need staking. They are ideal for large gardeners. Most beefsteak and cherry tomatoes are indeterminate.Select a site with full sun and, Dig the soil to about 1 foot deep and mix in aged manure and/or compost. Give it two weeks to break down before planting. Most gardeners purchase starter tomato plants from a nursery, due to the long growing season for a warm-weather crop. Harden off your own seedlings for a week before transplanting them in the ground. Set them outdoors in the shade for a few hours on the first day. Gradually increase this time each day to include some direct sunlight.

TransplantingTransplant your seedlings (or your nursery-grown plants) into the ground outdoors after all danger of frost has passed and the soil is at least 60°F. Place tomato stakes or cages in the soil at planting. Staking and caging keep developing fruit off the ground (to avoid disease and pests) and also help the plant to stay upright. When you transplant tomatoes, add a handful of organic tomato fertilizer or bone meal (a good source of phosphorus) to the planting hole. Do NOT apply high nitrogen fertilizers such as those recommended for lawns, as this will promote luxurious foliage but can delay flowering and fruiting.When planting seedlings, pinch off a few of the lower leaves.

Growing Tomatoes in Containers

Use a large pot or container (at least 20 inches in diameter) with drainage holes in the bottom.Use loose, well-draining soil (e.g., at least 12 inches of a good “potting mix” with added organic material).A tray of some sort should be placed under the pot to catch any excess water that drains out the bottom.Choose bush or dwarf varieties; many cherry tomatoes grow well in pots. Taller varieties may need to be staked.Plant one tomato plant per pot and give each at least 6 hours of sun per day.Keep soil moist. Containers will dry out more quickly than garden soil, so check daily and provide extra water during heatwaves.

GROWINGWatering: Water in the early morning so that plants have sufficient moisture to make it through a hot day.Water generously the first few days that the tomato seedlings or transplants are in the ground.Then water with about 2 inches (about 1.2 gallons) per square foot per week during the growing season. Deep watering encourages a strong root system.

Avoid overhead watering and afternoon watering. Water at the base/soil level of a plant to avoid splashing water on the leaves (which invites disease).

Mulch 5 weeks after transplanting to retain moisture, keep soil from splashing the lower leaves, and control weeds. Apply 2 to 4 inches of organic mulch such as straw, hay, or bark chips.

To help tomatoes through periods of drought, find some flat rocks and place one next to each plant. The rocks prevent water from evaporating from the soil.

Fertilizing: You should have already worked compost into the soil before planting and added some bonemeal to the planting hole when transplanting.

Side-dress plants, applying liquid seaweed or fish emulsion or an organic fertilizer every 2 weeks, starting when tomatoes are about 1 inch in diameter (some folks say “golf-ball-size”). If you are using an organic granular formula such as Epson Tomato-Tone (4-7-10 or 3-4-6), pull mulch back a few inches and scratch 2 to 3 tablespoons fertilizer around the drip line of the plant. Water in, and replace the mulch.

Continue fertilizing tomatoes about every 3 to 4 weeks until frost.Note: Avoid fast-release fertilizers and avoid high-nitrogen fertilizers. As stated, too much nitrogen will result in lush foliage but few flowers and little or no fruit.

Pruning, pinching, staking:

If growing vining tomatoes, pinch off suckers (new, tiny stems and leaves between branches and the main stem). This aids air circulation and allows more sunlight into the middle of the plant.Gently tie the stems to stakes with rags, nylon stockings, twine, or soft string.As a plant grows, trim the lower leaves from the bottom 12 inches of the stem.

PESTS/DISEASESTomato ProblemsIf no flowers form, plants may not be getting enough sun or water (too little can stop flowering).If plants produce a lot of flowers but no fruit, the cause might be inadequate light, too little water or inconsistent watering, too cold or hot temperatures (above 75°F at night/90°F during the day), or not enough pollinators (bees).If flowers form but drop off the plant, this is due to high daytime temperatures (over 90°F). Provide shade during the hottest part of the day by using row covers or shade cloth.Low humidity can also affect pollination; the ideal is 40 to 70 percent. If humidity is low, mist the plant to help pollen to stick.

Tomato PestsTomatoes are susceptible to insect pests. To avoid overpopulation of insect pests, follow these basic tips:1. Monitor tomato plants daily, checking under leaves, checking fruit, and checking near the soil.2. To dislodge many pests like Aphids, spray plants with a good jet stream from the hose.3. Handpick insects bigger insects like Tomato Hornworm with gloves on, dropping them into a bucket of soapy water.4. Apply insecticidal soap directly to the insect on the plant; this works for smaller pests such as aphids and spider mites.

5. Apply horticultural oils or sprays diluted in water. Neem oil sprays block an insect’s air holes.6. If you choose as a last resort to use insecticides like Sevin, keep in mind that you may be killing beneficial insects as well

Tomato Diseases•Blossom-End Rot causes the bottom side of the tomato to develop dark, sunken spots, due to a calcium imbalance.

•Early Blight is a fungal disease that causes leaves to drop. In July, the risks of blight increase, due to the combination of high humidity and warm days and nights. It starts with dark, concentric spots (brown to black), about 1/2-inch in diameter on the lower leaves and stems. If you catch it early and destroy infected leaves, your plant may survive. The best defense for outdoor tomatoes is good ventilation and stripping off the lower leaves as the fruits develop helps this, as well as helping the ripening tomatoes have maximum exposure to the sun.

•Late Blight is a fungal disease that causes grey, moldy spots on leaves and fruit which later turn brown. The disease is spread and supported by persistent damp weather. Unfortunately, once your tomato has late blight, there’s really no solution

•Mosaic Virus creates distorted leaves and causes young growth to be narrow and twisted, and the leaves become mottled with yellow. Unfortunately, infected plants should be destroyed (but don’t put them in your compost pile).

•Fusarium Wilt starts with yellowing and wilting on one side of the plant and moves up the plant as the fungus spreads. Unfortunately, once this disease strikes, the plant needs to be destroyed.

•Powdery Mildew is a fungal disease that leaves white spots or a dusting of white on the leaves. It can be managed.

•Cracking: When fruit growth is too rapid, the skin will crack. This usually occurs due to uneven watering or uneven moisture from weather conditions (very rainy periods mixed with dry periods). Keep moisture levels constant with consistent watering and mulching.

HARVESTING•Leave garden tomatoes on the vine as long as possible.•Harvest tomatoes when they are firm and very red in color, regardless of size, with perhaps some yellow remaining around the stem. Harvest tomatoes of other colors (orange, yellow, purple, or another rainbow shade) when they turn the correct color.•If temperatures start to drop and your tomatoes aren’t ripening, use one of these methods:1. Pull up the entire plant, brush off the dirt, remove foliage, and hang the plant upside down in a basement or garage.2. Place mature, pale green tomatoes stem up, in a paper bag and loosely seal it. Or wrap them in newspaper and place them in a cardboard box. Store in a cool (55°F to 70°F), dark place. Cooler temperatures slow ripening; warmth speeds it. Check weekly and remove soft, spotted, diseased, or ripe fruit.•Never place tomatoes on a sunny windowsill to ripen; they may rot before they are ripe!

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