Rotation key to organic vegetable gardening

Rotate the crops in your vegetable garden to help control pest and disease 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.

• The containers that you are going to use for seasonal plantings should have at least one bottom hole for drainage. A layer of gravel in the bottom of the container is not necessary to improve drainage. Fill the container with a lightweight, fast-draining soilless mix and avoid using heavy garden soil even if you amend it with compost. Leave enough space between the top of the growing medium and the lip of the pot to make watering easy. Very large containers can be partially filled with wood chips, plastic bags filled with packing peanuts or empty plastic pots turned upside down (my favorite method) to conserve the soilless mix. Separate the wood chips from the growing mix with landscape fabric.

• Plants that have been grown in containers should be moist when planted in your garden. When you remove the plant and its root ball from the container, spread out or cut all the roots that have encircled the root ball. These roots have grown in a circle inside the container and could eventually girdle or choke the plant if not redirected to grow out and away from the plant. This will help the new plant get established in the ground more quickly. Monitor watering needs carefully after planting, as the lightweight container soil can dry out quickly and stress the plants. Generally, containerized plants need more frequent, but light watering to get them established with roots growing out into the garden soil.

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