Issue: July 19, 2008

Carrots not growing may need better soil


I live in Alamogordo, and am trying to raise carrots. I have tried growing them in my garden plot and also in pots. They grow only 3" if I am lucky and some of them have shapes similar to an hourglass. I have tried purchasing "long" carrots as was stated on the package, and also "short" carrots.

Would growing spurts cause the hourglass shape? Can you suggest something I may be doing wrong? I am sure the carrots I am growing are not what were intended by the seed companies!

Barb R.
Alamogordo, NM


Your problem growing carrots is probably related to the soil. The soil should be well loosened and amended with compost. Rocky soil is often the cause of misshapen carrots. The rocks interfere with the growth of the carrot roots. They cause forked roots, twisted roots, and other shape abnormalities.

If your soil is not rocky, it may just be too hard for the carrot roots to properly form. The addition of organic matter in the form of well decomposed compost creates a soil that is better adapted for carrot growth. Deep digging when incorporating the organic matter is very helpful. The soil should be loosened more deeply than the length of the carrots you plan to harvest. The shorter forms may be a good choice while you are developing the quality soil that you need to grow good carrots.

It would be wise to have your soil tested to determine the nutrient and mineral salt levels. When you submit a soil sample for testing, be sure to tell what you intend to grow in that soil. You can get information regarding soil testing and where to send your soil sample from your local NMSU Cooperative Extension Service office.

There is an insect that feeds on the roots of carrots. This may be the cause of the hour-glass shape. If the insects chewed around the middle of the root, that would produce the observed effect. Uneven soil moisture, as you have suggested, can also result in poor carrot root formation. The organic matter recommended above will help the soil hold moisture and maintain the even levels of moisture needed for good carrot root development.

It is not too late to plant again. When you purchase seeds, look at the information on the packet that tells how long it will take for the crop to mature. Add a week or several weeks to that time for an extended harvest and schedule planting according to this information. In the case of carrots, you can cover them with straw when cold weather comes in your part of the state and continue harvesting from under the straw for an even longer harvest period. You will note that as the soil cools, the carrots will become sweeter. Summer planted carrots for a fall harvest are a great idea.

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:, 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, or at the Desert Blooms Facebook.

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