Poinsettias are traditional Christmas flowering plants whose blooms will last throughout the Christmas season. And with proper care, poinsettias may be grown on to flower again the next year.
When selecting a poinsettia, it is recommended to choose a plant that has dark green foliage; as fallen or yellow leaves indicate poor fertilization or a root disease problem. Flower bracts (red, pink, or white) should be of good size and have little or no pollen showing on the actual flowers (those red or green button-like parts in the center of the colorful bracts). The plant should be well wrapped when taken outside for the ride home; exposure to low temperatures for even short periods of time can cause leaves and bracts to turn brown and fall.
During the Holiday season, poinsettias should be placed near a sunny window or other well lighted areas, where they do not touch cold window panes. A temperature between 60 degrees and 70 degrees F. is desirable; higher temperatures will shorten the life of the flower bracts. Plants should be kept away from drafts (radiators, air registers, and open windows or doors). In order to preserve the blooms for the maximum length of time, plants should be placed in a cooler area (55 to 60 degrees F.). The soil should be examined daily and watered only when dry. Water should be applied so as to soak the soil to the bottom of the pot, and excess water should be discarded. If there is not enough water applied, the plant will wilt and the lower leaves will drop. If too much water is applied, the lower leaves will yellow and then drop. A soluble fertilizer is recommended, such as is used on house plants, once a month according to the recommendations of the manufacturer.
After the Holiday season, the plant may be kept and will bloom again the next. If the plant is too large for the old pot, it should be repotted a larger pot. The soil mix recommended is a mix of 2 parts garden soil, 1 part peat moss, 1 part sand, vermiculite, or perlite, and 1 tablespoon of superphosphate. This mixture, when thoroughly mixed in with each pot-full of soil makes a good mixture for poinsettias. After the danger of spring frost is past and night temperatures exceed 50 degrees F., sink the poinsettia pot in the ground to the rim in a will-drained, slightly shaded position out-of-doors. Between July 15 and August 1, the terminal portion of all shoots should be cut off. These can be rooted in a mixture of half peat moss and half sand, and flowered for Christmas using the procedure described next.
Fall care of poisettias is crucial to assuring beautiful Holiday blooms. The poinsettia plant should be taken inside before the first frost (usually around Sept. 15 in lower Michigan), and placed in a sunny window as before. In order to flower a poinsettia, you must keep the plant in complete darkness between 5 p.m. and 8 a.m. daily from the end of September until color shows in the bracts (almost mid December) Temperatures should remain between 60 and 70 degrees F. If this procedure is followed, the poinsettia will be in flower for Christmas.
The growth cycle of the poinsettia is as follows: DECEMBER: Full bloom. FEBRUARY: Flower fades. Lateral growth starts. MARCH : Remove flower. Cut stems to 6 inches. Many laterals will start below break. JUNE 1 : Repot in larger pot if necessary. Plant outside in pot. JULY : Pinch all lateral shoots to 4 inches. Root shoots if desired, then pot. E AUGUST: Take inside.
SEPT.20 TO DEC.1: Keep in light only from 8 a.m. to 5 p.m.
REFERENCE: William H. Carlson and J. Lee Taylor Department of Horticulture Extension Bulletin E-554