Heirloom tomatoes grow from seeds that are open-pollinated, meaning they have not been hybridized. They come from stock that is unchanged through generations of seed collecting. Heirloom tomato plants are called "indeterminate" because they continue to grow and produce fruit throughout the season. Heirloom tomatoes are harvested successively through the summer months. Hybrid varieties have a pre-determined height and the fruit comes to harvest all at once. Gardening with heirloom tomatoes is easy when you understand a little bit about their nature and their needs.
Gardening with Heirloom Tomatoes
Choose a garden spot that gets six to eight hours of sun per day and is near a water source. Grow heirloom tomatoes 15 to 20 inches apart. If you are going to let them sprawl rather than stake them, allow 24 to 36 inches between plants. Heirloom tomatoes grow to a height or length of 8 to 10 feet.
Use a shovel to turn over the garden soil. The soil should appear dark brown and have a loose, crumbly texture. Good soil is 20 to 30 percent humus, which is decomposed organic matter. Add compost to the soil to create a loose, porous mixture. Add two shovels full per 1 square foot. Composted soil retains water more easily.
Plant heirloom tomato seedlings with soil up to the first set of leaves. As the plants grow, pinch back unwanted suckers from the base area. Do not let suckers grow in the notch between the stem and branch as the plant develops. Place a tomato cage over each plant or a stake between two plants. As the plants grow they can be tied to the stakes or supported by the cage.
Add one shovel full of compost as a side dressing when the tomatoes are ¾ inch in diameter. Feed heirloom tomato plants with a half shovel full of compost one time per month of the growing season. Use this as a side dressing. Compost provides a slow, steady supply of nutrients to the soil.
Water heirloom tomatoes thoroughly once a week. Their root systems are deep, so shallow, frequent watering is not as effective as deep soaking. Add a 3-inch layer of straw or compost as a mulch to help retain soil moisture.