Choose plants wisely to manage pests

Reduce or eliminate the need to use pesticides in your garden by choosing plants carefully, planting them properly and monitoring them attentively. Together, these practices are part of a plant-care philosophy called “integrated pest management.”

Begin by choosing the proper plant for your site. When possible, select plants that are resistant to common diseases. Learn what your plants need and give them the appropriate care to minimize problems.

Use good planting practices, such as amending the soil with compost and planting at the proper depth.

Monitor all plants carefully for signs of insects and diseases. If trouble arises, identify the problem before taking any action. If you decide the damage is not tolerable and the problem warrants it, use the least toxic control measure. Timing also is important; apply controls at the time in their life cycle when pests and diseases are most susceptible.

Seek expert advice to choose the right control measures. For example, contact the Plant Information Service of the Chicago Botanic Garden (chicagobotanic.org/plantinfoservice).

Never spray just because you see insects. Most insects are beneficial or harmless. When you use an insecticide, you kill the good insects along with the bad ones.

When using power equipment such as a string trimmer in the garden, wear protective glasses and long pants. The plastic line can kick up debris that could injure your eyes or sting your legs if you are wearing shorts. The line can injure the bark of trees, so keep the string trimmer well away from them. It can even strip paint from fences.

Power equipment can be loud, so wear ear plugs any time you use it. Ear protection is especially important if you are using it for an extended period of time. I use ear muffs when mowing the lawn and when I use a leaf blower.

Pinch fall-blooming plants such as chrysanthemums and hardy asters in early June to control their size and increase production of flowers. Pinching will induce side branching, producing bushier, stockier plants. Make the first pinch when the plants are 6 to 8 inches high by removing approximately 1 inch from the tip of each shoot. When the resulting lateral branches reach 6 inches, pinch them.

These plants should not be pinched later than July 4 in the Chicago area, as late pinching can delay or prevent flowering.

Mowing is one way to control weeds when you are establishing a large naturalistic prairie area in your garden. Native plants typically develop their roots first, not their foliage or flowers, as they are getting established in their early years. That can give fast-growing weeds the opportunity to gain a foothold and choke out the native plants.

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