August 5, 2017
1 - Blueberries are extremely difficult to grow in New Mexico and not recommended, but some gardeners love a challenge.
Yard and Garden August 5, 2017
When is it best to transplant a blueberry bush? How do I get rid of grasshoppers on my blueberry bush?
Rio Rancho, NM
Some New Mexico gardeners really like a challenge. Blueberry plants provide just such a challenge. In addition to dealing with issues common with other plants, such as insects, New Mexico gardeners who try to grow blueberries must also contend with the fact that blueberry plants need a very acidic soil. New Mexico soils are usually alkaline, the opposite of acidic. It is not impossible to grow blueberries in New Mexico, but extremely challenging. The blueberry plants prefer a soil pH of 4.0 to 5.0, a difficult pH to create and maintain in New Mexico. Even in states with soils closer to a proper acidity, gardeners are often advised to grow blueberries in containers so that the soil acidity can be more easily provided. That is good advice for New Mexico gardeners as well.
Regarding the time to transplant blueberry plants - the best time is in the autumn after they enter dormancy and in the late winter or early spring just before they leave their dormant period. The advantage of fall transplanting is that many woody plants continue root growth in the autumn when the air is cold, but the soil has retained heat. In New Mexico, autumn is usually less windy than spring so plants are less likely to blow over or to be dried out by the winds. Blueberry plants have shallow root systems, so the mulch is extremely important for protection from drying and extreme temperature changes in the shallow soil.
Organic mulch will help maintain the acidity of the soil that you must create by adding organic matter and soluble sulfur. As organic mulch decomposes it creates carbon dioxide and water. When carbon dioxide dissolves in water it creates a weak acid, especially helpful in the case of many garden plants, but not enough to keep New Mexico soils acidic enough for blueberries. Irrigation with acidified water will also be necessary. The safest way for New Mexico gardeners to acidify their water is to use acetic acid (vinegar) and pH test strips (available in scientific supply stores) to adjust the pH of the water to about 3.5 to 4.0.
Container gardening allows you to create an acidic soil more easily, protect that soil from alkalinity in surrounding soil, and will allow you to repot in fresh acidic soil as the alkaline New Mexico irrigation water alters the acidity of the soil.
Regarding the grasshoppers – that is another difficult problem. It may be easier to cover the plants with row cover fabric to keep the grasshoppers from the plants than to kill the grasshoppers. Grasshoppers are migratory and will come in from some distance. Most New Mexico home gardeners do not have access to grasshopper breeding grounds to treat with pesticides and it is generally not an economical process. In a home garden, protecting the plants makes more sense, but it may be possible to plant a “trap crop”, plants that the grasshoppers will go to first that you will treat with insecticides. This may reduce the numbers of grasshoppers finding the blueberries, but will probably not be sufficient to provide the protection you need. The row cover fabric will also provide protection from intense New Mexico sunlight and from birds who want to share your blueberry crop with you.
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: firstname.lastname@example.org, office: 505-865-7340, ext. 113.
For more gardening information, visit the NMSU Extension Horticulture page at Desert Blooms.
Please copy your County Extension Agent and indicate your county of residence when you submit your question!