How to Trim Poinsettias

Poinsettia plants don't require very much water and in some U.S. climates can survive winter outdoors, though in most place these southern Mexico natives are enjoyed as holiday houseplants. Poinsettias need pruning attention throughout the year. For healthy, bright red flowers -- actually modified flower petal-like leaves -- and thick, green leaves, trim your plant throughout the year. Snipping off diseased leaves and managing larger stalks help promote better overall poinsettia health.

Pruning shears

General purpose fungicide

During the spring and summertime, poinsettia plants are susceptible to mildew growth. Mildew-damaged leaves rarely recover, so snip them off at their bases to prevent spreading. Mildew appears as powdery or fuzzy white spots. Poinsettia plants feature particularly dense leaf structures, so it's important to catch mildew spots before they spread through the close structure. Fungicide can help prevent future mildew outbreaks.

Cut out damaged branches at a 45-degree angle during winter. Poinsettias remain active in winter, and flowers may even develop while snow is still on the ground in mid to late winter. Pruning off snow-damaged branches helps the plant retain crucial nutrients as it undergoes wintertime growth.

Trim periodically during winter and spring flowering season, maintaining 2-foot stalks. Poinsettia bud growth and flowering diminishes when stalks extend beyond 2-foot maturity.

Deadhead in late spring to promote new bud growth for next season. Dead flowers will lose their color and wilt. These sickly flowers continue to suck nutrients from the plant as they die, so remove them once late-spring wilting begins.

Prune the plant heavily at the end of the growing season, once all the dead flowers are removed. So-called "hard cutting" is beneficial for many perennial plants. To promote active regrowth, the "Pruning Handbook" recommends leaving only two or three poinsettia buds intact after the flowers have died .