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How to Grow Productive Tomatoes

Updated: Jul 11

6/18/2024


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Overview

  1. Choose productive varieties.

  2. Provide at least 8 hours of direct sunlight, and rich and well-draining soil.

  3. Spade compost into the garden bed.

  4. Do a soil test ($20/sample) and follow soil test recommendations for fertilization.

    1. If soil is not tested, apply 5-10-5 fertilizer according to package directions.

  5. Water 1 ½ inches per week.

    1. Deep watering encourages healthy roots.

    2. Water at the bottom of the plant to prevent splashing onto leaves.

    3. Water early in the day so plants can dry off.

  6. Mulch around plants with tree leaves, other organic materials, or landscape fabric.

    1. Mulch prevents splashing of disease organisms onto the leaves when irrigated, controls weeds, moderates soil temperature, and reduces evaporation.

    2. 2-4 inches deep.

    3. Apply mulch about 1 month after planting, mulch cools the soil; soil needs to warm up first.

    4. Do not use lawn clippings treated with herbicide.

  7. Optional: Pruning for indeterminate plants only: stop when fruit forms. Leave enough foliage to prevent sun-scald. May prune excess growth on indeterminate plants. Missouri pruning – remove growth beyond 1st set of leaves on side shoots/suckers -provides more leaf cover, less sun-scald.


Growing Tomatoes

Starting Plants Indoors Correctly

  • 6 to 8 weeks prior (end of March).

  • Pay attention to soil temperature, soil media, and light (location and duration).

  • Stretched plants are weak due to inadequate light.

  • Harden off (toughening); 7-10 days.


Buying Plants

  • Limited selection at local vendors. Special, unique, unusual varieties are only available with seed.

  • Healthy, deep green, no dying/yellowing leaves, stocky, no more than 8-10” tall, stems pencil thick.

  • Examine for dead roots, badly encircling roots, or soil pests.

  • Remove any fruit or flowers, which slow production – root growth comes first.


Planting and Spacing

  • Soil MUST be warm, at least 60F.

    • Cold soil will stunt the plants (last frost date, Saint Paul, 05/15).

      • Wait until night temperatures stay at 55F for 10 days.

      • NOTE: clear plastic will speed soil warming.

  • Space 18” to 36” apart, depending on the support system and mature plant size.

  • Remember to loosen roots when planting.

  • Use starter fertilizer.

  • Tomatoes are unique, and develop more roots if the stem is buried.

    • Plant deep, pinching off the lower-most lower leaves to encourage root growth.

    • Plant lanky plants in a shallow trench after letting them bend upward for 24 hours by laying the pot on the side in the sun.


Planting in Containers

  • Use a commercial potting soil that is sterile with no disease, insects, or weed seeds.

    • Garden soil compresses in containers, squeezing out O2 and H2O from roots, encouraging disease and other problems.

  • Place containers in a location that gets full sun.

  • Containers may require watering 1-2x daily, depending on heat, humidity, pot size, and pot color.

  • Containers need regular fertilization because nutrients tend to flush out the bottom of the pot.

  • Do not let the pot bottom contact native soil.


Supports

Add at time of planting.

  • No Supports

    • Plants lying on the ground lead to diseased fruit and insect damage.

  • Trellis

    • Strings between wires

    • Prune off suckers until the first fruit starts forming.

  • Florida Weave

    • Twine weaved around plants.

  • Cages

    • Use large cages with large open spaces to pick fruit

    • Most store-bought cages are too flimsy.

  • Stakes

    • At least 6 ft tall, 1 ft. deep

    • Prune off suckers until the first fruit starts forming


Problems with Growing Tomatoes

Use Integrated Pest Management


Weeds

  • Use mulch

  • Avoid herbicides (can damage tomato plants).

  • Some tomato roots are shallow so be careful if hoeing.


Insects

Notably the Tomato Hornworm. Hand-picking, covering plants, water spray.


Diseases & Disease-like Symptoms

  • Bacterial

  • Fungal

  • Viral

  • Abiotic


Disease Prevention

  1. Choose disease resistance varieties.

    1. VFN Verticillium, Fusarium, Nematode resistance.

    2. A (or ASC) Alternaria Stem Canker

    3. F Fusarium Wilt

    4. St Stemphylium Grey Spot Leaf

    5. T Tobacco Mosaic Virus

  2. Optimal growing conditions and good air circulation.

  3. Garden sanitation – remove weeds & dead tomato leaves, do not compost diseased plants, and control insects.

  4. Rotate crops. Avoid planting in the same spot for 3-4 years. (tomato, pepper, eggplant, tomatillo, ground cherry).

  5. Grafted plants.

  6. Water only at the base of the plant early in a.m. to keep foliage dry.

  7. Do not work in the garden if the foliage is wet.

  8. When plants are 24 inches tall, remove all leaves that might touch the ground.

  9. Use landscape fabric or organic mulch to cover soil to reduce soil splash and foliar disease.

  10. Try container gardening.


Harvesting and Storage

  • Remove top 4” stem of indeterminate tomatoes 1 month before first fall frost – helps fruit to ripen.

  • Never refrigerate tomato fruit.

Favorite Varieties

(Joe) Tommy Toe

(Jennifer) Tennessee Suited


List of Tomato Seed Vendors

The following vendor seed list is not comprehensive. It is not an endorsement of any listed vendor. It is not a criticism of an unlisted vendor. It is a list of those suppliers with whom we have good experiences. Even if you do not grow tomatoes, it's fun to read about the many varieties.


When you run across an unfamiliar vendor for any plant or seeds, check with Dave’s Garden Watchdog before ordering. “The Garden Watchdog is a free directory of 8,132 mail-order gardening companies. Here gardeners share their opinions on which companies really deliver on quality, price, and service.” Some vendors may not be listed.


Vendor List

  • Baker Creek Heirloom Seeds. Offers a large collection of heirloom, open-pollinated, and rare seeds.

  • Bounty Hunter Seeds. Very large collection of rare and unusual open-pollinated varieties.

  • Fruition Seeds. A small collection of mostly open-pollinated varieties. A few varieties from the Cornell breeding program.

  • Harris Seeds. A collection of hybrid varieties with a small selection of open-pollinated seeds.

  • Johnny's Selected Seeds. Many hybrid varieties, some developed by the company, and some open-pollinated varieties. A large online reference library for gardeners.

  • Pinetree Garden Seeds. A large collection of hybrid and heirloom varieties. Fair prices. Seed packets contain fewer seeds than other vendors, an advantage for the home gardener who wants just a few plants of a variety.

  • Seed Savers Exchange. Started the movement to save heirloom vegetable varieties from extinction. Good selection that varies from year to year.

  • Seed Treasures. A Mom-and-Pop operation in northern Minnesota with a surprisingly good offering of heirloom and open-pollinated seeds.

  • Totally Tomatoes. A large collection of open-pollinated varieties, some quite rare and unusual. Well-written descriptions.

  • Tomato Growers Supply Co. Almost 400 varieties of tomatoes of all types.

  • Victory Seed Company. A large selection. Many of the new tree-type/dwarf indeterminate varieties are listed.


Joe Baltrukonis RCMG Volunteer

Jennifer Porwit RCMG Volunteer


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