Ornamental cabbage is an easy-to-grow hybrid flowering plant that produces red, pink, and white blooms in the cooler weather; in fact, they are able to survive in temperatures as low as five degrees Fahrenheit. They are edible, although they are not as tasty as regular cabbage, and are mainly planted for ornamentation. Since they are low growers, they are often planted as edging plants.
Ornamental cabbage must be started in the late summer to early fall to get the best blooming. It is often used as a replacement plant in gardens and flower boxes for summer plants that are gone or dormant in the colder weather.
Plant the seeds six to eight weeks before the first frost is expected. Use eight-inch pots and fill them with commercial potting soil that retains water. Space the seeds five inches apart and do not cover them with soil, as they require light to germinate. Your Ornamental cabbage should begin growing in just ten days. Wait for night temperatures to fall in to the range of forty to fifty degrees; the blooms will not turn colors until temperatures are consistently below sixty degrees.
If you purchase the plants from a nursery, transplant them into your garden in September. If you plant too early, they will grow leggy and will not change color. Buy the larger plants, as the cabbages will become root-bound and the top portion will become stunted. Plant them in the ground about twelve to eighteen inches apart in a sunny area with nutrient-rich soil that will remain moist but also well-drained (in fact, the bottom leaves should actually touch the soil). Water well and cover the soil with mulch to retain moisture. Use a water soluble 20-10-20 fertilizer after the cabbage is planted or a slow-release fertilizer before planting; use two pounds per hundred square feet of plantings.