Issue: July 15, 1996


Starting new grape vines

Question: What is the technique for propagating grapes from cuttings?

Answer: During the summer, grapes may be propagated using leafy cuttings. Stems of recently matured growth cut about 18 inches long may be rooted if they are treated with root-inducing growth regulators and kept under high humidity. High humidity is a problem in New Mexico unless you build a propagation bed with a mist system to frequently moisten the cuttings.

Use of the process called layering will probably be more successful and may also be done in the summer. In this method of propagating the vines, the cutting is induced to form roots before it is severed from the parent plant. The vine must be bent to the ground. This vine should then be wounded by cutting it slightly, girdling it, or wrapping wire tightly around the stem. Treat the wounded area with root-inducing chemicals and bury the wound in good garden soil or potting soil. After several weeks, roots will form. Next spring, just before growth begins, this rooted vine may be severed from the parent plant and moved to its permanent location.

Another form of cutting that is successful may be accomplished in the late winter with dormant vines. Vines about one-half inch in diameter and one to one and one-half feet long are severed from the plant. The basal portion of the vine should be treated with root-inducing chemicals. These cuttings should then be placed in good potting soil or garden soil so that only one bud remains above the soil. Keep the vines well watered, and they should form roots as the leaves begin to develop. By the end of the summer or the next spring before growth begins, the vines may be transplanted to their permanent location in the garden.


Plants won't grow, too much fertilizer

Question: Things that used to grow in my garden won't grow for me any more. I could grow beets and beans, but now they only grow a few inches, turn yellow and then die. Other things, okra, tomatoes, and squash, do just fine. I have tried moving my garden, still no success. Soil test results indicated that I had too much fertilizer. I stopped fertilizing, still nothing grows. What can I do?

Answer: The soil test information provides valuable information in identifying your problem. You say too much fertilizer has been applied. That means there is an excess of fertilizer and natural soil salts in the soil. Fertilizers can create salty conditions in the soil. Beets and some other garden crops, such as beans, are sensitive to excess salt in the soil, especially while young. Tomatoes and some other garden crops may to be less sensitive. If you choose to stop using commercial fertilizer and change to manure, you can actually aggravate the problem even more rapidly. Unless the manure has been well composted and exposed to moisture so that the salts common in manure have been washed away, manure can rapidly increase the saltiness of the soil.

Salts can be leached from the soil if the garden area is heavily irrigated several times and the soil allowed to drain well below the root zone of the crops. Gypsum applied to the soil before heavy irrigation can help leach some of the more harmful salts from the soil. In areas where drainage is poor, leaching will not work. The water must drain away to carry the salts from the garden. Addition of compost, especially compost made without manure, can also help alleviate salt problems in the garden.


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 and the NMSU Horticulture Publications page.

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

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

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