Berries, Orchid Diseases

Q: We recently received a gift of homemade jam s made with home-grown boysenberries and blackberries. It was so good. How hard is it to grow berry plants? I know I can make the jam. --F.S., La Habra

A: Cane berry plants will tolerate almost any type of soil as long as it drains well. They grow best in deep, rich soil and in full sun. For good yields, they should be watered regularly. The real key to success is annual pruning. Canes that bear fruit should be cut back each year. Pruning also helps to balance and distribute the fruit load. Cane berry plants produce fruit the second year on canes that grew the previous year.

Q: Every one of the leaves on our cattleyas has spots, and no one seems to know why. Do you have any ideas?--G.S., West Los Angeles

A: Many orchid diseases result in leaf damage of some sort, and there are even more types that harm the flowers. Plants infected with rust fungus, for instance, have pustules of powdery orange spores on the underside of the leaves. If you keep the leaves from getting wet, that condition can be eased. In severe cases, treat the uninfected leaves with the fungicide Zineb. Another fungus that attacks orchid leaves is leaf spot, which causes sunken, reddish-brown spots to form. Like many other fungus diseases, leaf spot is favored by overly moist conditions, so again, keep the leaves dry. Mottling of the leaves is characteristic of virus infection. Because most virus diseases that affect orchids are propagated with the plant, infected plants should be destroyed.