December 27, 2014

1 - Maintaining the beauty of a poinsettia into the spring is possible if the proper environment is provided.

Yard and Garden December 27, 2014

Q.
I bought several poinsettia plants and would like for them to keep their leaves and flowers as long as possible. Some of my friends have had beautiful poinsettias well into spring, but mine always seem to drop their leaves before Valentine's Day. What can I do to make them look good longer?

J. B.

Santa Fe

A.

Poinsettias (Euphorbia pulcherrima) can be challenging to maintain after the holidays. They are sensitive to environmental stresses and will drop their leaves in response to stress. Since their "flowers" are actually bracts, colorful leaves, these bracts may also be lost after exposure to stress. Even if the bracts, and associated small yellowish flowers above the bracts, do persist, loss of the lowers leaves detracts from the beauty of the plant.

Stresses that cause leaf drop include drying and temperature stress. Even though the poinsettia grows natively in some dry environments, its response to drought is to drop leaves to conserve water and safe the rest of the plant. In home environments, the plant should be watered regularly and not allowed to dry. The dry air of most heated homes causes rapid drying of plants.

Temperature stress may also cause problems for poinsettia plants. These plants are native to tropical environments and respond to non-freezing low temperatures by dropping leaves. However, keeping them in fairly cool rooms may prolong their beauty. Very high temperatures increase drying. A room maintained between 55 and 75 degrees will give best results.

The poinsettia plants need light to maintain their health. Direct sunlight will increase heating and drying, but indirect bright light will prolong their beauty. A south window with sheer curtains will provide this type of bright-light environment.

They will not need fertilizer until growth resumes in the spring. As growth resumes old leaves may begin dropping. You may choose to discard them at this time, or, if you enjoy the challenge, you may try to carry the plants through the summer and induce new flowers next fall. However, the plants grown in this manner rarely look as good and new plants produced by professionals in greenhouses.

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.

Links:

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

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

Please copy your County Extension Agent and indicate your county of residence when you submit your question!