Start ornamental peppers indoors in small individual pots filled with potting soil or seed-starting medium. Bury the seeds ¼ to ½ inch (6 mm. to 1 cm.)  deep. Allow one to two weeks for the seeds to germinate and another six to eight weeks for the seedlings to reach transplanting size. Begin feeding the seedlings with half-strength liquid fertilizer at two-week intervals about three weeks after they germinate if you have planted them in seed starting medium. The medium manages water well and helps prevent fungal diseases such as damping off, but it doesn’t contain nutrients the plant needs to grow.

Good potting soils contain enough nutrients to support the plant until transplanting time. Transplant the seedlings into a sunny part of the garden with organically rich, well-drained soil. Space the plants according to the directions on the seed packet or plant tag, or about 12 inches (30+ cm.) apart. If you prefer to grow your ornamental peppers in containers, use 6- to 8-inch (15 to 20 cm.) pots filled with good quality general purpose potting soil.

Read more at Gardening Know How: Ornamental Pepper Care: How To Grow Ornamental Pepper Plants https://www.gardeningknowhow.com/edible/vegetables/pepper/grow-ornamental-pepper-plants.htm