January 9, 2010

1 - You can purchase potting soils for different kinds of plants with different needs.

Yard and Garden - January 9, 2010


After reading some of your old articles about repotting houseplants, I thought I would try it. Is now (January) a good time to transplant houseplants? What potting soil should I purchase?

- Allie R.


January is an excellent time to transplant many common houseplants. Houseplants are often plants from tropical regions without the distinct dormancy period experienced by our outdoor, temperate zone plants. For this reason, we can transplant them now and expect them to grow well. Some tropical plants do experience dormancy during a dry season in their native habitat, and these plants will transplant best just after new growth begins. Look for signs of new growth in your plants to determine if they are ready to transplant. New growth will often indicate readiness to form new roots. New root development is important for successful transplanting.

The proper potting soil depends on the type of plants you grow and their specific water requirements. Potting soil manufacturers have created numerous potting soil types and labeled them for the houseplants we commonly grow. Some plants cannot tolerate drying. Potting soils for these plants are usually composed of compost and/or peat moss. Other plants cannot tolerate too much moisture. These plants need a soil with more air space and better drainage. Potting soils for cacti and succulents often contain material to increase drainage.

Experienced gardeners may often make their own potting soils, but many have decided it is easiest to purchase potting soils. They often find that under their conditions, they develop a preference for a specific brand or type of potting soil. Try several and see if you find a favorite for the types of plants you grow and the conditions under which you grow them.

Purchased potting soils have a few advantages over home-made potting soils. They are usually pasteurized (heat treated to kill most disease organisms). Of course, once you open the package any bacterial and fungal spores in the air can enter the potting soil. Purchase what you will use in a relatively short time to avoid this problem. Purchased potting soils often contain some added plant nutrients (another way the potting soils are formulated for specific plants). These nutrients are often present in a slow-release form that provides nutrients to your plants for several months. This reduces the need for you to provide fertilizers for at least a few months and helps the plants get off to a good start after transplanting.

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.

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!