Issue: June 15, 1996


Tomato dispute

Question:My neighbor and I have an ongoing argument. Is it better to stake tomatoes and pinch out the suckers, or should I just leave them alone and let them produce as many suckers as they want and let them lie on the ground?

Answer: There is a third option - let them produce the suckers, but grow them in a tomato cage. That's my favorite. I prefer not to pinch out the so called suckers, branches that form at the base of leaves. That is extra work and reduces the number of leaves on the plant. Here in New Mexico the greater the number of leaves to cover the fruit, the less damage we have from sun scald. Sun scald is the result of our intense sunlight shining directly on the shoulder of the fruit and burning it. A white patch develops. As it ages, it turns brown or black and fungi begin rotting the damaged area. This fruit is not edible, even if you cut the damaged portion off. The fact that fungus is growing in it requires that, for safety reasons, you dispose of the fruit. Besides, it doesn't look too appetizing.

Pinching to allow only one stem results in delayed tomato production. Plants grown to only one stem produce fewer but larger tomatoes. If you are attempting to grow "bragging rights" tomatoes, you may wish to pinch. You will need to do something to prevent sun scald of your monster tomatoes.

Plants allowed to sprawl on the ground are more likely to produce rotted fruit if the fruit lie on the ground and the soil is kept moist. Caging helps grow plants upright, using less space per plant and reducing fruit contact with the soil and rotting.

Caging also allows earlier planting as the cage can be wrapped with spun-bonded row cover material, cheese cloth, or other material to protect against late frosts. Other benefits gained from wrapping the cage are wind protection and protection from the insects that spread curly-top and tomato spotted wilt viruses.


Cucumber vine problems

Question: My cucumber vines aren't making cucumbers. What am I doing wrong?

Answer: Maybe nothing - you may just be impatient. Cucumbers, like squash, pumpkins, watermelons, cantaloupes, and many other plants produce male and female flowers separately on the same plant. They often begin producing male flowers several weeks before the females appear. The males make pollen and are necessary, but they do not produce the fruit. Look and see if there is a little cucumber behind the flower. If you see the baby cucumber, you have female flowers. If you just see a slender stem going right up to the back of the flower, you are looking at a male flower.

If your plants have female flowers and the fruits still aren't setting, be sure that the plants are not drying excessively between irrigations. On hot days, the leaves may wilt but should recover as the temperature drops in the evening. If they are still wilted by morning, you are not watering enough, or you are watering too shallowly and too often. Be sure to encourage deep rooting so that there are good absorbing roots deep in the soil where they are influenced by the daily heating of the shallow layers of soil. A mulch may also be helpful once the vines are large enough to be resistant to sowbug damage. Deep watering and mulch may help.

Excessive nitrogen fertilization is also a possibility. If the nutrients are imbalanced, the flowers will drop. If this is the case, side-dressing with phosphate fertilizer will help bring the nutrients back into balance. To do this, use a spading fork or otherwise make holes in the ground a few inches deep so that the phosphate will be in the soil near the roots, not on the surface. Phosphate fertilizer is not as soluble as nitrogen and cannot be washed into the soil with irrigation. Don't use a hoe or otherwise damage the roots of your cucumbers when applying the phosphate.

Finally, there may be a bee problem. Tiny parasitic mites have attacked many of our wild bees in the state, killing the hives. Without bees to pollinate your cucumber flowers, you will have to transfer pollen from the male flowers to the female flowers by hand. Use a cotton swab or soft bristle paint brush to transfer the pollen. Make sure other factors aren't the problem first. This involves a lot of work.


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!

www