Tomatoes are a favorite garden vegetable, but in Eddy County they can be somewhat challenging. There are several factors that result in failure of tomato plants to form fruit or do well.
One common factor is that many varieties (the larger fruited varieties in general) cannot set fruit in hot weather. The pollen is killed by the heat and cannot successfully pollinate the flower. Or, the generative nuclei of the pollen are unable to move from the stigma (where pollen is received) through the style (stalk connecting stigma to the ovary). Failure of the generative nuclei to successfully move from stigma to ovule (and failure to have viable pollen) results in failure of the generative nuclei to fertilizer the egg cell in the ovary. As a result, no fruit will form. Why heat and size of the tomatoes effect this process in not clearly understood. But in general the larger the tomatoes the harder it is to get fruit in Eddy County.
Pick a moderate size tomato when planting. Always select a variety that has VFN after its name.
This is, Verticillium wilt, Fusarium wilt and Nematode resistant.
When the weather is cooler as may perhaps occur after monsoon rains begin, the fruit may begin to form. Many years ago some new varieties of tomato were bred by Texas A&M to form fruit in the heat of summer. “Saladette” was one of the first of these. I have noticed several varieties in the nurseries with names that imply that they will form fruit in the heat. I have tried some of these with some success. I have also had success with “Heritage,” an older variety. These form medium sized tomato fruits that are big enough to be good with sandwiches and salads.
The really large “beefsteak” types tend to delay forming fruit until late summer and into the autumn. Cherry and pear tomato plants produce small fruit that are good for salads and other meals where small size is not a problem. These smaller types tend to successfully form fruit even during the hot part of summer. Experiment with several varieties, especially those known to produce fruit in the heat. You may find varieties that work well in your garden environment. Keep a garden diary so you know what works and what does not.
I also plant on the North side of the house in the shade, this is the opposite of what most garden books state, but this is Eddy County not Ohio.
Another trick is to shade the plants to reduce the heat the plants receive.
Tomatoes need about 4 to 6 hours of sunlight each day, but light shade, especially in the hottest part of the day (afternoon) will increase the chances that the tomatoes will produce fruits for you. This also helps prevent curly top virus which is transmitted by an insect, beat leaf hoppers. Leaf hoppers prefer to feed in sunlight so normally won’t feed in the shade.
Some gardeners have problems with tomatoes because they are too generous. These gardeners tend to over fertilize their plants. Excess nitrogen fertilizer (the first number on a fertilizer bag) causes excessive growth. The plants look healthy and grow wonderfully, but they produce few flowers and no fruit. Adding additional phosphate fertilizer to the side of the plants may help them form fruit. Phosphorus is a mineral that encourages flowering and fruit formation in plants. (Phosphate is the second number on a fertilizer bag.) Also blossom end rot, which is when a dark watery spot form on the bottom of the fruit. This is a result of irregular watering or calcium that is unavailable to the plant. See https://aces.nmsu.edu/pubs/_a/A231/welcome.html.
Avoid growing tomatoes and related plants (eggplant, chilies, and such) in the same location each year since they deplete the nutrients and may result in accumulation of disease organisms specific to these plants in that area.
Alternate tomatoes with beans, corn, squash, and other non-solanaceous crops (tomatoes are in the plant family Solanaceae).
Article originally published in Focus on Artesia and Focus on Carlsbad 2019: Summer Editions.