My first attempt at growing zucchini squash failed because a bird or rat stole the seed. Now I plant the seeds in small containers and place them in a netted area waiting to be transplanted. On my second attempt, the plants grew well but finally died, succumbing to the powdery mildew (PM) fungus. Next, I planted PM resistant varieties. This helped, but I still had to assist the process with fungicidal sprays. This points out that the word “resistant” means just that; it doesn’t mean immune! It could also mean that in tests, the resistant variety simply did ‘better’ than nonresistant varieties.
Well, the bird or rat problem seemed to be solved; the PM problem was solved or semi-solved, and a new crop was growing well. The plants were blooming, and young fruit was setting. I was excited. I had small fruit developing on the plant, but then, they dropped off. This was an attack of the dreaded pickleworm! So I threw some 3/4-inch bird netting over the plants. This will keep most of the pickleworm moths out but allow bees to come in and pollinate.
The next day, I went out into the garden to pick some nice zucchini for dinner. I observed that the whole plant was dying. It looked like a virus, one of several that attack squash — squash mosaic virus (SMV), cucumber mosaic virus (CMV) and watermelon mosaic virus (WMV). These different viruses are transmitted by insects which feed on virus-infected squash plants or some nearby weeds. Once the plants are infected there is nothing that can be done for the plant, and the virus disease will eventually kill the plant. The best preventive measures include insect control along with host weed management.
These viruses have a wide host range, infecting a variety of vegetables (cucumbers, peppers, tomatoes, squash) and ornamentals (gladiolus, zinnias and chrysanthemums). Symptoms include distortion of the leaves, pronounced chlorotic mottling and a dark green mosaic pattern. Infected fruit coming from such plants show a strong mottled pattern.
For those that produce an abundance of zucchini, and other squash, my hat is off to you!
Note: Squash, along with melons and cucumbers (cucurbits) are unique vegetable plants that bear two kinds of flowers on the same plant, male and female. In order to produce fruit, the pollen from the male flower must be transferred to the female flower. Insects do the major pollination work. Female flowers can easily be distinguished from the male by the presence of a miniature fruit at the base of the flower.
Sometimes gardeners are concerned because none of the first blooms produce any fruit. This is because the first flowers produced on the plants will be male and cannot give forth fruit. In time female flowers and subsequent fruit will be produced.
Trellis your cucumbers
Depending on the variety, cucumbers can be grown as a bush or vine. Many gardeners purchase the vining variety and let the plants run. There is, however, an alternative. Put them up on a trellis. The disadvantages to doing this are extra labor and costs, but most gardeners don’t mind the labor. The other disadvantage is living in windy areas; they are more susceptible to wind damage. The advantages, on the other hand, have merit. They are higher yields, easier harvesting, better pest and disease management, straighter fruits, uniform color, fewer soil diseases, and lastly, a trellis will allow for more plants to be planted per area.
Hilo resident Nick Sakovich is a professor emeritus of the University of California. He has worked in the field of agriculture for 30 years. Email your questions to Sakovich at firstname.lastname@example.org.