How to Grow Tomatillos

Tangy, husk-encased tomatillos (Physalis ixocarp) are go-to ingredients for salsa verde, chili and a fiesta of other Latin-American dishes. Where summers are dry and warm, tomatillo plants begin producing their green or purple fruit in midsummer and continue until the first fall frost. Wait until a month after the last spring frost date before planting tomatillos. To ensure cross-pollination and fruit set, grow at least two of them. Treat them as you would their tomato (Lycopersicon esculentum) relatives.

Tomatillos require at least six hours of daily sun and loose, well-draining soil. For the best results, loosen the top 6 to 8 inches of soil with a spade or tiller and work in a 2- to 3-inch layer of organic compost at planting time. Amend an area large enough to space your tomatillos 3 feet apart; the Cornell University Department of Agriculture estimates using 150 to 225 pounds of compost for each 25 square feet planting area. Also work in 3 cups -- or the manufacturer's recommended amount -- of granulated, 5-10-10 tomato fertilizer per 25 square feet, and water the planting bed well.

Tomatillos root along their stems, so plant them with only the top one-third of their stems above the soil line. Even deep planting, however, doesn't eliminate their need for support. Without it, the sprawling stems root to the soil's surface, where their fruit is difficult to harvest and prone to rotting in wet conditions. Supply extra support with standard tomato cages, or secure the plants to 5- or 6-foot trellises with soft, stretchable material such as polyester. Retie them periodically as they grow.

For a maximum fruit harvest, fertilize tomatillos once a month with 5-10-10 tomato food from the time their flowers appear until the end of the growing season. Sprinkle 1/2 cup, or the label's specified amount, of the granules evenly around the base of each plant. Keep the fertilizer at least 4 inches from the stems, scratch it lightly into the soil's surface and water thoroughly.

Tomatillos need at least 1 inch of water every week. During very hot spells, increase that to 2 inches. These amounts are roughly equivalent to between 16 and 32 gallons of rain or supplemental water per 25 square feet of soil. Water slowly, so the soil has time to absorb the moisture and hydrate the roots. To retain moisture, discourage weeds and improve the soil, maintain a 2- to 4-inch mulch of straw, grass clippings or other organic material around the tomatillos.

If buckshot-sized holes riddle tomatillos' foliage, flea beetles are responsible. The pests are most likely to attack young tomatillo seedlings in early spring. Clear the bed of weeds and debris that shelter the overwintering beetles, and plant only large, vigorous nursery-grown tomatillos. Periodically till the soil around the plants to destroy the beetles' eggs and larvae.