Bell peppers come in green, red, orange, yellow, purple and even black varieties. They all start out green and change color as they mature. Bell peppers are heat-loving vegetables that are native to the Americas. They are widely available in spring as small transplants, but a wider choice of varieties is available if you start your own peppers indoors from seeds.
Start seeds of bell peppers indoors four to six weeks before the average date of your last spring frost. Sow the seeds in individual, 2-inch pots filled with indoor potting soil. Keep the soil moist until germination, which usually occurs in 7 to 14 days. Grow the seeds under fluorescent lights kept 3 inches above the tops of the plants.
Harden off transplants beginning two weeks before the last spring frost. Put them outdoors in the shade for a longer period each day. After a few days, put them in direct sun for a longer period each day until they are outdoors in full sun all the time. Bring the plants indoors if frost threatens.
Prepare the garden bed. Spread 2 to 3 inches of compost and 1 inch of well-rotted manure in the planting bed. Turn over the soil with a shovel to incorporate the compost and manure. Rake the vegetable bed smooth.
Transplant the pepper seedlings 18 to 24 inches apart in rows that are 12 to 16 inches apart. Dig a hole slightly larger than the root ball of the seedling with a garden trowel. Insert the roots in the hole, then back fill with soil and firm the surface gently around the stem.
Water each pepper plant individually with a hand watering can after transplanting to help it settle. Provide the plants with the equivalent of 1 to 2 inches of rainfall per week.
Mulch the soil in the garden bed around your bell peppers with partially decomposed compost, shredded leaves or hay. Spread a 2-to-4 inch layer around the plants and in the rows. This helps conserve moisture and control the growth of weeds.
Fertilize monthly by spreading granulated fertilizer around the base of the plants. Pull back the mulch and spread the fertilizer in a 6-inch circle around the plant, following manufacturer's instructions for quantity. Replace the mulch.
Harvest the first few peppers each plant produces to encourage them to produce even more peppers as the season progresses. Leave a few on the plant to mature and turn red (or orange, purple, yellow or black) after midsummer.