Fruit or vegetable, now that is the question! Much confusion exists around tomato’s classification, but that doesn’t make homegrown tomatoes any less delicious. Believed to have originated in South America, the tomato plant has made its way up through Mexico to the US and Canada and even to Europe via Spanish conquistadors, where it has since become a beloved ingredient in all manner of cuisines. While the “fruit” part of the plant is clearly edible, the rest of the plant is, in fact, toxic and should be grown somewhere away from small children and furry friends who have a tendency to explore the world with their taste buds. The tomato plant comes in a plethora of varieties which vary in shape, color, size, and taste, so we recommend investigating all your options and selecting varieties that cater to your preferences prior to growing!
The Costoluto Genovese tomato is an indeterminate heirloom type from Italy that’s well adapted to high heat but also does well in cooler weather and coastal climates. The large, red, flattened and deeply ribbed fruits have a complex, slightly tart flavor. Slicing will produce cool scallop-edged rounds perfect for sandwiches or snacking. Often used for making sauces, soups, or juice, this is a good choice to grow for cooking or preserving because the flavor intensity will only increase with heat.
Seed Depth: 1/4″
Space Between Plants: 18–36″
Space Between Rows: 24–36″
Germination Soil Temperature: 70–90°F
Days for Germination: 6–10
Sow Indoors: 5–7 weeks before average last frost date.
Sow Outdoors: After all danger of frost has passed and soil is at least 60°F. Only recommended if your growing season is long.
Vegetative: Can be easily propagated by taking root or stem cuttings or by layering. Cuttings will root in an aeroponic system or soilless media.
Grows best in warm weather. Be sure that you plant early in areas with short summers to allow time for ripening before the first frost. If your summer is extremely hot (regularly over 90°F), some light shading will help tomatoes stay happy. This variety will still remain productive at temperatures up to 95°F. Not frost tolerant.
Natural: Full sun.
Artificial: Grows best under HID lamps due to their need for tons of light. Use metal halide for the vegetative growth and switch to high pressure sodium when you want the fruit to start forming.
Soil: Prefers a well-drained loamy or sandy soil with a high amount of organic matter. A pH between 6.0 and 6.5 will keep plants healthy and nourished.
Soilless: Start seeds and root cuttings using a soilless mix.
Hydroponics: Thrives in a variety of hydroponic systems, including NFT, slab, and media-based systems. Use perlite or mineral wool as the growing medium.
Aeroponics: Cuttings will root in aeroponic systems.
Water: Requires moderate levels of water. Once established, they are fairly drought tolerant. Even soil moisture is necessary to prevent cracking fruits and blossom end rot. Avoid getting water on the leaves.
Nutrients: Requires high levels of nutrients. Amend soil with compost and aged manure before planting. Fertilize 3–5 times during the growing season using a balanced liquid fertilizer, compost tea, and/or liquid seaweed.
Pruning: Remove suckers—the auxiliary buds that form at the intersection of leaf and stem—to divert that energy into fruit production.
Mulching: Use mulch to conserve soil moisture. Black landscaping fabric can be helpful in warming the soil more quickly and allowing for earlier planting in addition to suppressing weed populations.
Support: Indeterminate varieties need staking, trellis, cages, or another type of support for best results.
Disease(s): This variety has resistance to bacterial leaf spot and botrytis. Still, watch for:
Deficiency(s): A calcium deficiency can lead to blossom end rot. To remedy, try adding a small amount of crushed eggshells to the soil around the base of your plant.
Rotation: A 3-year rotation away from all plants in the Solanaceae family is recommended. Plant after a cover crop or nitrogen-fixing legume like peas or beans. If nematodes are a problem, plant after tilling marigolds into the soil.
Companions: Grows well with basil, asparagus, beans, bee balm, borage, carrots, celery, chives, cucumber, garlic, lettuce, marigolds, mint, nasturtium, onion, parsley, pea, pepper, and sow thistle. Avoid dill, corn, kohlrabi, potatoes, apricot, fennel, cabbage, and cauliflower. Don’t plant tomatoes under walnut trees.
Harvest: Pick fruit at the peak of ripeness when there is no green or orange color left for the best taste. Check plants daily or every other day to make sure you don’t miss any ripe tomatoes. They don’t need sunlight to ripen, so be sure to reach all the fruits in the middle of the plant. Wear long sleeves and gloves when harvesting to protect your skin from potential irritation that some people experience after contact with tomato leaves. This variety is known to ripen well even after picking, so if your fall frosts arrive when fruits are still green, snip off the fruiting branches and hang them in a warm, well-ventilated area to allow fruits to continue their ripening off-plant.
Storage: Keep fresh tomatoes at room temperature for 2–3 days for the best taste. Handle gently and store ‘upside down’ with the stems carefully removed. If you can’t eat your entire harvest, we recommend preserving tomatoes rather than refrigerating them, since this alters the texture of the fruit.
Fun Fact: The Italian word costoluto in the name of this variety refers to its ribbed shape, so any veggies with this name will display a similar shape characteristic.
History: Thomas Jefferson was a fan of this tomato variety, planting it in his Virgina garden starting in the late 1700s.
Seed Saving: To save heirloom tomato seeds, select tomatoes at their peak ripeness (not too soft and not too firm) that display characteristics you value (e.g., size, shape, color, heartiness and/or taste). Cut your tomatoes in half, scoop out the seeds and jelly-like liquid inside, and place in a jar. Add about ½ a cup of water and put jar in a dark location for 3—4 days until the seed coatings separate from the seeds. As this happens, viable seeds will sink to the bottom of the jar. If a mold forms on top of your jar, don’t be alarmed! This is a natural part of the process and will not negatively impact your seeds. Pour off the top layer of the mixture (the mold, seed coatings, etc.) and place the seeds that are left in a strainer and rinse. Lay out seeds on a cookie sheet or coffee filters to dry, and then store in an airtight jar until ready for use!
Preserve: Tomatoes are easy and fun to can as sauce, cubes, or peeled and whole. Green tomatoes can be made into a chutney or salsa and canned or pickled.
Prepare: Can be used to make sauces, salsas, ketchup, and soup, or used raw in salads or on sandwiches. Green tomatoes are delicious sliced, breaded, and fried. This type is preferred for cooking but is also delicious eaten raw.
Nutritional: Provides high levels of vitamin(s) A and C. Also a good source of B vitamins, potassium, and calcium.
Medicinal: Tomatoes contain lycopene, an antioxidant compound that is currently being investigated for its cancer fighting and cholesterol lowering abilities. Lycopene may also help your skin protect itself from UV damage. Regular consumption may also help protect against heart disease.
Warnings: Tomato leaves can be a skin irritant for some, so wear long sleeves and gloves when harvesting.
Follow these guidelines for making a Garlicky Heirloom Tomato Sauce and can or freeze any extra for sauce year round.