Heirloom tomatoes are varieties that have been grown for a long time, most of which originated in Europe. While many heirloom tomatoes are not disease resistant like more recent hybrids, gardeners still grow heirlooms for their superior taste and appearance. Tomato plants can be purchased from a plant nursery or garden store, or you can start your heirloom tomatoes from seed. Seeds should be started inside the house 6 to 8 weeks before planting, and require a little more effort than planting store-bought seedlings.
Start your seeds indoors about 6 weeks before the last frost. Fill seedling pots or peat pots about three quarters full of light potting soil. Do not pack the soil; keep it light for good water drainage. If you chose to buy your plants from the store, skip to Step 5.
Press one to three seeds into each pot, pushing the seed about ½ inch below the surface of the soil. Cover your seeds with dirt, and place pots on a large try to catch water drainage. Water each pot thoroughly. If you are using peat pots, be sure the peat is completely soaked.
Cover your tray with plastic wrap or a clear plastic bag. The plastic will keep in moisture and warmth, which will help encourage germination. Place your tray under a grow light or in a warm, sunny location. Check your pots daily, watering the soil when it appears dry.
Remove the plastic when you see seedlings poking through the dirt. Continue to water your seedlings as needed until the weather is warm enough to plant.
Prepare the ground for planting after the danger of frost has passed and nighttime temperatures stay above 55 degrees F. Choose a location with full sun (at least 6 hours per day) and good soil drainage. Use a garden fork to loosen the top layer of soil, and mix a few inches of compost in with the dirt.
Dig holes large enough to accommodate your plants' root systems, leaving plenty of space between each hole. Large heirloom varieties need up to 4 feet between each plant, while dwarf plants can be placed 1 foot apart. Check the directions on your seed packet or the information card that came with your tomato plants for specific spacing instructions.
Plant your seedlings in their holes. Tip the pots upside down to remove the seedlings, using one hand to support the base of the plant and the root ball. Peat pots can be placed directly in the ground. Cover the roots with soil and water the ground thoroughly.