The Best Dirt for Tomatoes

Soil Preparation

• Analyze the soil into which your tomato plants will be transplanted and make necessary adjustments. If the soil is sandy or light, it will drain too rapidly for the tomatoes to benefit from the water. Conversely, soil that is full of clay or exceptionally heavy will hold too much water and cause the roots of the plants to rot. According to the National Gardening Association editors, both types of soil can be improved with the addition of organic matter, such as compost or well-rotted leaves or grass clippings." Peat moss is also a common soil enhancer. The additives make light or sandy soil more water-retentive and loosen up heavy soils to promote drainage. The Gardening Association also advises that you work the soil with a tiller or garden fork to a depth of 6 to 8 inches so the roots will be able to expand easily.

Best pH Levels

• The alkalinity or acidity of soil is measured by pH levels, with 7.0 being neutral. Tomatoes grow best in slightly acidic soil with pH levels between 6.0 and 6.8. Since pH levels vary, check them every three to five years with a pH testing kit available at garden centers, nurseries and university cooperative extension service centers. If the pH level is too low, mix some lime into the soil. Adding sulfur to the soil will correct high pH levels. Test the pH levels after adding components to the soil and make adjustments until the pH is correct. Additives mixed with soil in the fall allow them to slowly mix in with the other soil components.

Fertilizers

• Fertilizers make a big difference for tomato plants. They give the plants a strong start and keep them on a good growth track until harvest. About 6 to 8 inches below the earth or at the bottom of a container, place a thin layer of commercial or organic 5-10-10 fertilizer. In lieu of fertilizer, you can use rotted leaves, compost or dehydrated animal manure. Before transplanting the tomato plants, cover the fertilizer, rotted leaves, compost or dehydrated animal manure with 2 to 3 inches of soil to keep the tomato roots from touching the fertilizer, which has salt in it, which can leach moisture from the roots and impede growth. According to the North Carolina Cooperative Extension, you can also "sidedress tomato plants with 2 to 3 tablespoons per plant of a complete fertilizer such as 8-8-8 or 10-10-10 after the plants have started to set fruit and 4 to 6 weeks thereafter throughout the growing season. Keep the sidedressing material 4 to 6 inches from the plant's stem to avoid fertilizer burn."

Starter Solutions

• To give young tomato plants a healthy beginning, use a starter solution to guarantee they get the best fertilization during their early growth. You can buy pre-made starter solutions at nurseries and garden centers or make your own. Mix a complete fertilizer such as 8-8-8 with water. If you are growing many plants, mix a pound of fertilizer with 10 gallons of water. For smaller tomato crops, use 3 or 4 tablespoons of fertilizer for each gallon of water. Limit the fertilizer solution to 1 cup per transplant as using more will burn the tomato plants’ root systems.