Issue: December 6, 1999

Poinsettia leaves fell off

I have a question about poinsettias. What do you do when the leaves fall off? Will they grow back? Will they be the same color, and should they be stored in a dark place?

I have a question about poinsettias. What do you do when the leaves fall off? Will they grow back? Will they be the same color, and should they be stored in a dark place? Ron via Internet

If the leaves have fallen at this time of the year, it will be of little use for holiday decoration. The plant will begin to grow after several weeks to a couple of months depending on the environment where it is kept. However, it will not produce the red bracts (the red leaves that surround the little yellow flowers) in time for Christmas.

If this is a new plant that has lost its leaves, the cause is environmental stress - temperatures which were too low, or the plant was allowed to dry too much. It would be best to replace the plant. It is also important to determine the cause of the leaf drop so that the problem may be remedied.

It is possible that the plant was stressed during shipment; however, the problem occurs more commonly once the plant has been brought into a home or an office. It was grown in a greenhouse until it was ready for sale. Once it is purchased, it is often taken to a warmer, darker, drier, environment. Under cool conditions, less than 80 degrees during the day and down to about 60 degrees at night, moisture and light are of less importance (though still important). As temperatures increase, light and moisture in the air become more important. Of course water in the potting soil is also important. At higher temperatures the plant dries more rapidly, so a warm, dry, dim environment is the worst possible situation and may result in loss of leaves.

Too much water can also cause problems. The poinsettia is adapted to dry conditions and readily drops its leaves to reduce dessication; however, overwatering can quickly cause root rot which results in too little water getting to the leaves. This will also result in leaf drop and is much more likely to cause the death of the plant.

If possible, provide for most of the time the poinsettia is kept for decoration - keep it in a cool, humid, brightly lighted room. For parties and other times when it is used for decoration, it may be brought into the warmer, drier, and dimmer environment - just don't try to keep it there too long. If it must stay in this less desirable environment, pay special attention to watering before the soil dries completely, but not too often. If possible, place other plants nearby so that collectively they may increase the humidity around the plants. Another solution is to purchase the plant only a day or so before it is needed for decoration.

There are also other Yard and Garden articles on poinsettias available from the NMSU College of Agriculture website.

Marisa Y. Thompson, PhD, is the Extension Horticulture Specialist, in the Department of Extension Plant Sciences at the New Mexico State University Los Lunas Agricultural Science Center, email: desertblooms@nmsu.edu, office: 505-865-7340, ext. 113.

For more gardening information, visit the NMSU Extension Horticulture page at Desert Blooms and the NMSU Horticulture Publications page.

Send gardening questions to Southwest Yard and Garden - Attn: Dr. Marisa Thompson at desertblooms@nmsu.edu, or at the Desert Blooms Facebook.

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