Red peppers can take more time to grow than green varieties, with many taking up to 100 days to fully mature. However, some varieties can turn red in as soon as 65 days and will easily grow in a range of climates. Once you have purchased or gathered the red pepper seeds of preferred variety, it's best to begin the planting process after the last frost in your area. Red peppers grow best after the soil has warmed.
Add 1 tbsp. of trisodium phosphate, 3 tsp. of 5-percent chlorine bleach and 1 quart of warm water to a large bowl or container. Add your red pepper seeds to the mixture and allow them to soak for at least 15 minutes. This will kill any disease and soften the hull of the seed to speed germination. The bleach and TSP should not be necessary if using store-bought seeds.
Rinse the seeds in cool running water for at least five minutes. Let the seeds dry on a paper towel after rinsing them.
Add medium potting soil to a plastic-tray potting kit. Leave at least 1 inch of space between the soil and the rim of the potting areas. Water all of the soil so that it is slightly moist.
Add the red pepper seeds to the top of the soil and then cover the seeds with a ½ inch of potting soil. Cover the potting tray with its clear plastic top or with plastic wrap.
Place the tray on the top of your refrigerator, or other warm area, to start the germination process. Remove the covering of the tray every day during germination to make sure soil is moist. Gently water as needed.
Wait for up to one week for the red pepper seedlings to sprout, then transplant the strongest seedlings to 4-inch pots. Place the pots in an area that receives sunlight, such as a windowsill, or under fluorescent lights until it is warm enough to plant the red pepper seedlings outdoors.