By Rebecca Jepsen
for the Mercury News
Add a layer of mulch around trees and shrubs to retain moisture, provide nutrients and deter weeds. Apply a 2- to 3-inch layer of organic matter or chipped tree trimmings; prevent rot by keeping it several inches away from the trunks of the plants.
Control earwigs that feed on soft plants and can cause significant damage. They feed at night and hide in moist, tight spaces during the day. Trap them by setting out moistened, tightly rolled newspaper at night, then discard it in the morning. Check out other control methods at the UC Earwig Pest Note.
Fire blight shows up in the spring, causing blackened branches and twigs that look like they've been scorched. It often affects fruit trees such as apple, pear and loquat, as well as toyons, hawthorns and crab apples. Spread by insects, rain and pruning, fire blight left unattended can kill the tree. Prune the infected branch about 8-12 inches below the visible damage. For more information, go to the UC Pest Note.
Prevent rust on snapdragons, sunflowers, sweet peas and pansies by avoiding overhead watering and practicing good sanitation. Rusts are easily identified by the dry, brown, orange or yellowish spores that form on lower-leaf surfaces. Upper-leaf surfaces of heavily infected plants can become spotted or turn yellow or brown. Remove and destroy affected plants or plant parts as soon as they appear. Fungicides, such as neem oil, can be applied at the first sign of infection.
For our complete list of May gardening tips, click here.
What to plant now
Transplants: cucumber, tomatoes, peppers, squash, eggplant, beans, lettuce, and many herbs such as dill, basil, chives and mint.
Seeds: corn, beans, summer squash, beets, radishes, spinach.
For a list of warm-season vegetables that do well in Santa Clara County, go here.
- Rebecca Jepsen, University of California Cooperative Extension Santa Clara County Master Gardener.