Plan to rotate your crops to prevent disease

Rotate the crops in your vegetable garden to help control pest problems. This is the easiest way to practice organic, integrated pest management gardening.

Many insects and diseases attack vegetables within the same plant family. By planting vegetables from a different family in a problem area, you minimize the chances for a repeat infection.

The basic families include the cabbage family (broccoli, cabbage, cauliflower, Brussels sprouts, radishes and turnips); cucumber family (gourds, melons, squashes and cucumbers); nightshade family (eggplant, potatoes, tomatoes and peppers); goosefoot family (spinach and beets); onion family (leeks, garlic and onions); legume family (all peas and beans), and the carrot, celery and parsnip group.

• If you have a lot of digging to do in your garden, it's important to have your utilities located before starting the work. In the suburbs, call J.U.L.I.E. at (800) 892-0123 or 811 to have your yard marked for underground utilities (this is a free service).

The website is www.illinois1call.com. In Chicago, call DIGGER at (312) 744-7000. It generally takes two working days for these services to locate your utility lines, so allow plenty of time before digging. These locating services will not mark any lines you have installed yourself, such as a gas line to a grill or wires for landscape lighting. Dig carefully by hand if you are working within 18 inches of either side of any marked underground utilities. Also, take care when digging in gardens with underground sprinklers. The black polyvinyl pipe used in many home systems is very easy to cut with a shovel while PVC piping is more resistant to shovel damage.

• It's a beneficial garden practice to deadhead (manually pinch off spent flowers) of rhododendrons and azaleas after they finish flowering. This is also the correct time to prune their branches to reduce the size of the plant as needed. It is best to be conservative with pruning them back. You can increase the flower count for the following year by very carefully pinching off one-half of the sticky new green growth emerging from the spot where the flowers once were.

• Tim Johnson is director of horticulture at Chicago Botanic Garden, chicagobotanic.org.