Are Serrano Chilies Ready When They Turn Red?

Measuring Heat

• Capsaicin, a colorless and odorless waxy compound found in the white pith surrounding the seeds in a pepper's inner wall, causes the pungent heat. Since the more capsaicin in a pepper the hotter it will be. Chilies are classified by their heat, as measured on the Scoville scale, named for American pharmacist Wilbur Scoville, who originated the calibrations in 1912. The hotter a pepper, the greater the number of Scoville heat units (SHU) assigned to it. The scale ranges from zero SHU for a sweet bell pepper to bhut jolokia, Scotch bonnet and habanero peppers on the other end, all with over 100,000 SHU.

Serrano's Place

• About midway on the Scoville scale, the serrano chili pepper contains 8,000 to 23,000 SHU. The fruit ripens 75 to 80 days after planting. If you bite into a 23,000-SHU serrano, quickly counter it with bananas, milk, yogurt or granulated sugar for mouth relief. Among the pluses for serrano eaters, the pepper contains twice the vitamin C found in an orange. The capsaicin that can ignite your mucus membranes can also increase fluids in your stomach to improve digestion. It fights bacteria responsible for stomach infections, as well.

Growing for Heat

• Hot peppers like serranos need warm weather. With proper care and hot, humid conditions, each plant may yield 40 to 50 peppers during a long harvest season running from June to October. Plant in spring or early summer, at least two weeks after the last expected frost. In cooler climates, increase your yield by growing under row covers throughout the summer. Choose a site with full sun for hotter peppers, against a south-facing wall, if possible. During the time before flowers set, feed with a balanced fertilizer. Apply a vegetable plant food in an 8-4-4 ratio every seven to 10 days. Dissolve 1 tablespoon of the formula in 1 gallon of water, and soak the soil. Water steadily through the growing season. Mulch around the plants to keep the soil moist and warm.

After Harvest

• When harvesting, cut the fruit from the branches, rather than pulling. If you plan to dry any of your hot peppers, leave them on the plant until fully ripe. Cut with 1 inch of stem attached, and hang in a sunny place until dry and brittle. After drying, grind into flakes to season stews and soups. Use serranos raw in pico de gallo, salsa or guacamole. Add them to cooked sauces for Southwestern dishes. If fiery Thai peppers are too intense for your palate, substitute serranos in Thai cooking. Be careful when working with these peppers. Use disposable kitchen gloves, and especially avoid touching your eyes or nose. When finished with food preparation, wash your hands with vinegar or soap.