May 20, 2017

1 - Grape pruning is important for good production of fruit.

2 - There are several sources of information to determine the cause of seasonal pollen allergies.

Yard and Garden May 20, 2017

Q.

We have purchased a home which has a mature grape arbor (two varieties-trunks are 3-4"). When we first looked at the home last year both plants were heavily producing. We did not do any plant pruning over the winter (were looking for someone who knew what to do). This spring both plants came to life, one a couple of weeks later than the other. We are now concerned that the first plant is not going to produce fruit. While the second plant has gone on to produce berries the first plant remains with bunches of fuzzy material (and some small berries). Is there anything we can do to save this yield? Also can you recommend someone we can consult with on how to care for these plants?

- Warren H.

A.

You may want to contact your local NMSU County Cooperative Extension office. Your local NMSU County Extension agent can give you some good advice can look at your plants and determine if there is a specific problem and recommend measure to manage the problem. You may also find the following NMSU Extension publications helpful. Growing Grapes in New Mexico, Circular 483, and Pruning Grapes to the Four-Arm Kniffin System, Guide H-303. These publication should give you some ideas. Other publications about grapes and other fruit varieties may be found at aces.nmsu.edu.

You will notice that the instructions for pruning grapes recommend what seems to be extreme pruning. The reason for this is that grapes will direct much energy into growth at the expense of fruit production unless they are severely "disciplined".

The basics of grape pruning direct you for form a "trunk" and some "scaffold branches" as the basic permanent structure of the grape vine. Most instructions will be for vineyard pruning, but the specific for this, the number of trunks and scaffold branches can be modified for your specific circumstances. Once the basic structure is formed, you will have producing branches form from the scaffold branches each year. The flowers will be formed near the base of these producing branches, and then the rest of that branch will just form leaves. These leaves are important for producing sugars needed for development and ripening of the berries. However, since these vines may grow excessively, some growers will "tip" the branches about 3 feet beyond the flowers to prevent excess growth and direct more of the sugars into the crop.

Next spring the branches produced this year should be pruned back leaving only 2 to 4 buds next spring depending on the variety. These will then produce next year's producing branches. This is repeated every year. This seems to be extreme, but results in more fruit production and less vine production.

If you would prefer to hire someone to prune your grape vines, once again your local NMSU County Extension Service agent may be able to direct you to some experienced horticulture professionals to help you.

Q.

Would you be able to tell me what in the Las Cruces desert might cause itchy eyes and other allergic symptoms this time of year?

- Karen

A.

Since different plants bloom at different times in different parts of New Mexico, your local NMSU County Extension agent will be a good person to contact to learn what is blooming now. Your county’s Extension offices may be found at http://aces.nmsu.edu/county/. The Extension Service agent will know most crops, weeds, ornamental plants, and native plants that may be flowering in your area. Local allergy doctors may also be able to provide this information and test you to see to which pollens will cause allergic reactions for you.

Some newspapers also publish generalized lists of the plant pollens that are prevalent in specific areas. Even some online weather web sites will provide “air quality” or “allergy” alert information.

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!