- 1). Use liquid fertilizer after planting the seedlings in your garden (or when foliage is at least 3 inches high, if you started them in the ground from seed). To do this, carefully pour fertilizer in a circle at least 2 to 3 inches from the stem and gently disperse it into the soil with a watering can or garden hose.
- 2). Place tomato fertilizer spikes a few inches from each tomato plant. Do this approximately 2 weeks after initial planting and follow directions on the package regarding how many to use. Usually one to two spikes per plant, placed on opposite sides, is sufficient. Give the plants a deep watering after setting the spikes. The soil should be wet several inches down.
- 3). Replace the spikes when they have dissolved (after several weeks, depending on weather conditions) or use granular tomato fertilizer. Granules, like spikes, gradually feed the plants. If you use granules, use a garden spade or similar tool to work them several inches into the soil (no more than 4 to 6 inches) and water them well. Covering the granules with soil keeps birds from eating the granules and helps get the nutrients where they need to be. Don't place the granules too close to the plant; 6 to 12 inches away from the stem usually is best.
- 4). Feed plants at least once more when it is bearing tomatoes, unless granules are not dissolved or, if applicable, the fertilizer spike is still intact.
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