Plant of the week: peppers

Peppers require lots of sun, but will not produce well in extremely hot temperatures. (Courtesy of Ellen Nibali, Handout photo / July 23, 2008)

Every time baby squash in my garden starts to grow, it dies. I hose down the garden every day, but it still gets fuzzy and dries up. How can I stop this?

Most vegetables don't like wet foliage. Choanephora wet rot is a fungus encouraged by warm, rainy days with overcast, humid conditions. Overhead watering, watering too often, and plants crowding so they don't get good air circulation all contribute to choanephora. The fuzzy black or brown fungal growth occurs in squash and pumpkin blossoms, causing them to abort, or causing them to wither at the connection of the blossoms to the young fruit. The spores overwinter on dead plants and in soil and are spread to squash blossoms by insects and splashing water. Mulch plants with three to four layers of newspaper as a barrier. Water only at the base of plants, not on foliage. Discard infected blossoms and fruit. Pull off blossoms that stick to young fruit so the fungus can't get started there. At the end of the season, remove all plant residue.

Bark is separating from the trunk of my flowering cherry tree. What can I do? I don't see anything else, except some little protrusions from the bark that look like pencil lead, but they're very fragile and crumble when touched.

The protrusions you see are frass (sawdust and fecal matter) pushed out by an ambrosia beetle as it bores into the tree. Ambrosia beetles bore into many tree species, both stressed and unstressed. There are two generations yearly. The first does the most damage, though it is not necessarily fatal. But it's too late to treat your tree now. Prompt removal and destruction of infested trees is recommended.

University of Maryland Extension's Home and Garden Information Center offers free gardening and pest information. Call 800-342-2507 or send a question to its website at extension.umd.edu/hgic.

Plant of the week

Peppers

Capsicum annuum

What popular vegetable is really a fruit, comes in almost every color of the rainbow, was given its erroneous name by Christopher Columbus, its most popular variety contains none of the chemical for which the species is famous, and is planted in almost every kitchen garden in America? It originated south of our border, was taken to Europe, brought back to North America, and is now predominantly produced in China. If you answered "pepper," you are correct. Sweet bell peppers need well-drained but consistently moist soil. While they require lots of sun for flower and fruit development, they will not produce well with extreme hot temperatures for extended periods. Try to provide some afternoon shade. During heat waves, cool them with a mist of water. When flowers begin to develop, side-dress with a balanced fertilizer. Pinch off the earliest flowers to encourage more fruit production. Sweet peppers will be sweeter if allowed to ripen to red. Hot peppers can be harvested green or allowed to ripen and change color.

— Lewis Shell