How to Grow and Care for Thai Pepper Plant

If you're a chili pepper fan who enjoys some sweet with the heat you might try growing Thai pepper plant (Capsicum annuum 'Bird's Eye'). It grows thick-walled fruits 1 to 2 inches long and full of seeds. They ripen from green to red at maturity with a Scoville rating of 50,000 to 100,000. With a sweetness similar to a red bell pepper, they're very hot but not fiery as a habanero.

At about 1 foot tall, the Thai pepper plant grows well in containers. Some of the dozens of pepper varieties are sold as ornamentals which also are edible. This is a chili pepper with a long growing season, 100 to 130 days, that produces best in plenty of hot, humid weather.

How to Plant Thai Pepper Plant

To successfully grow and harvest these small, prolific peppers you need to provide day time temperatures of 75 to 80 degrees F. and a lengthy gardening season of at least 100 days.

When to Plant

Gardeners in hardiness zones 9 to 11 can direct sow seed when soil has warmed to 60 degree F. Otherwise, start seeds indoor 8 to 10 weeks before the final frost date in your growing zone.

Selecting a Planting Site

Choose a spot that receives full sun, 6 to 8 hours daily, with rich, well draining soil. Amend with compost or other nitrogen rich organic material. Avoid spots where other nightshade plants were grown the previous year.

Spacing, Depth, and Support

Transplant seedlings 1 to 2 feet apart in rows 2 to 3 feet apart. Remove seed leaves and set seedlings in planting holes at or slightly lower than the level in their current container. In raised beds seedlings can be planted 14 to 16 inches apart.

With a mature height of 1 foot, Thai pepper plants don't require support.

Thai Pepper Plant Care

Light

This hot pepper plant thrives in hot sun and needs direct sunlight a minimum of 6 hours daily. More is even better. Avoid planting near taller plants that block light.

Soil

Thai pepper plant prefers rich, well-draining soil with a slightly acidic to balanced pH of 5.5 to 7.0. Work aged compost or manure into soil before planting.

Water

Deep, thorough watering every two to three days keeps soil moist without waterlogging. When fruits are in the immature green phase be careful of overwatering but don't let soil become bone dry. Drip irrigation is ideal for keeping Thai pepper plant well hydrated.

Temperature and Humidity

This hot pepper requires steady heat of 70 to 85 degrees F, daily and 60 to 70 degrees at night. Nighttime temperatures outside this range can reduce your yield. Humidity levels of 50 to 60 percent are adequate as long as it still gets intense light and moist soil.

Fertilizer

Fertilize Thai pepper plant a month after planting out with an NPK 5-10-10. When fruit starts to set feed a second time with a product that includes calcium. Once plants are established, avoid nitrogen rich fertilizers which can inhibit fruit production. Tomato fertilizers work well for pepper plants.

Pollination

All pepper plants produce flowers with both male and female parts. However, wind and bees are needed to complete pollination. When your plant has plenty of flowers but fails to produce fruit, it may be due to an absence of pollinators in your garden. Adding flowers that attract them to the garden landscape improves fruit production in many crops, including Thai pepper.

Types of Thai Pepper Plants

Thai pepper plant includes 79 identified varieties, but classifications are a bit confusing depending on where they are grown, Here are several hot peppers comparable in size and heat.

• Serrano, Capsicum annuum: Ripe fruits are scarlet red, cylindrical, and 1 to 2 inches long. Thick fleshed with clean, biting heat, Three serranos equal the heat of one Thai pepper.
• Tabasco, Capsicum frutescens: Thin, bright orange-red fruits 1 to 1 1/2 inches long are thin-walled with a sharp, biting flavor.
• Korean, Capsicum annuun: Cousin to Thai pepper, this chile is bright green, slightly curved and thin fleshed. Korean hot peppers measure 3 to 4 inches and taper to a point.
• Cayenne, Capsicum annuum: Most often used dried, cayenne peppers are thin, 2 to 4 inches long and taper to a point. Ripe fruits feature bright red color and tart, smoky flavor.

Thai Pepper vs. Tabasco

Thai pepper and tabasco pepper are sometimes confused though they are different species. Heat levels are similar but the peppers taste different. Tabasco peppers have a greener flavor similar to celery and green onions while Thai peppers are sweeter with a flavor note similar to red bell pepper. Growing conditions are similar but tabasco peppers can be harvested sooner, ripening in about 80 days.

Harvesting Thai Pepper

Thai peppers are harvested in both the green and red stages. Wait until green peppers reach full size before picking. Green peppers will have lower heat levels and not have the same flavor as a fully ripe red pepper. Use a snipper to remove peppers from the plant to keep stems intact. Stemless peppers deteriorate quickly after being cut.

How to Grow Thai Pepper Plant in Pots

Thai pepper plant's small size and attractive fruits make it an ideal container plant.

Choose a 15-inch pot with good drainage and fill it with a quality potting mix combined with perlite, moss or coconut coir for moisture retention. Make a planting hole in the center for the seedling and plant at the same level or slightly deeper as in its seedling pot. Fill in around the roots, firming soil to keep the plant upright.

Water well and place the pot to receive full sun daily. Potted plants may need to be watered twice daily. Check soil with a moisture meter or poke your finger in about 2 inches. Never let the soil get completely dry, which can lead quickly to wilting. Fertilize every 4 to 6 weeks through the growing season once fruits begin to form using an organic liquid fertilizer.

How to Grow Thai Pepper From Seed

Due to its long growing season it's best to start Thai pepper seeds indoors 8 to 10 weeks before the final frost. You'll need a germination tray or small pots and potting or seed starting mix. A heat mat and artificial lighting can improve sprouting and early growth but aren't necessary.

1. Fill the germination tray or several small pots with moistened, well-draining potting mix. Soilless seed starter is a good choice for Thai pepper plants.
2. Plant seed 1/4 inch deep and cover with potting material.
3. Give the seeds lots of light and temperatures between 80 and 85 degrees F. Use a heat mat and artificial light, or place them in a south-facing window and cover with a plastic dome to increase humidity.
4. Keep soil moist but not soggy, watering when soil surface dries.
5. Seeds germinate in 7 to 21 days. Remove plastic when sprouts emerge.
6. Once seedlings have established strong roots, pot up into individual or larger pots with a well-draining potting mix.
7. When soil temperatures approach 60 degrees F. begin to harden off seedlings.
8. Transplant into the garden or 15-inch pots approximately two weeks following final frost.

Common Pests and Plant Diseases

Thai pepper plant attracts a number of sap-sucking insects like aphids and spider mites. When discovered early, these pests can be knocked down with a strong spray from a hose. Treat infestations with a mild soap and water solution.

The most significant pest, especially in the southern U.S., is the pepper weevil. It lays eggs in flowers and developing peppers. The larvae then tunnel through all parts of the plant, ruining the fruit. Once fruits are breached, insecticides won't fix it. Remove and dispose of any fallen fruit. Practice good garden sanitation and crop rotation, avoiding areas where solanaceous plants have been grown the previous two years.

Thai pepper is also vulnerable to fungal, bacterial and viral diseases. They include verticilllium and bacterial wilts, bacterial and cercospora leaf spot, powdery mildew, and pepper and tobacco mosaic viruses.

Treating affected plants with appropriate fungicides can help manage some issues; inorganic controls generally are ineffective against viral infection.

Reduce the likelihood of these problems by providing the best possible growing conditions and using disease-resistant seeds.