Grub control is generally applied by mid-July

Grubs can be a problem in lawns some years. Adult beetles will be attracted to irrigated lawns that are surrounded by dry lawns to lay their eggs in early summer.

If the season is dry and you are the only one watering the lawn on the block, you will have a greater chance of having grubs.

Your lawn may or may not have a problem with grubs this year, so deciding not to apply grub control will not necessarily result in a grub infestation. Typically, when there are 8 to 12 grubs per square foot, visible damage will occur as they feed on the roots of the grass.

A grub-infested lawn with root damage will brown out later in season when hot and dry weather increases stress on the lawn. Raccoons and skunks will dig in lawns for the grubs — this is often the first sign of grubs.

Be sure to read the label carefully to make sure you are using the right product at the right time of year. Products designed to prevent grubs are generally applied late June to mid-July. There are products designed for quick kill of grubs and are applied later in season when grubs reach a threshold in the lawn that is causing damage.

There is no need to control a small number of grubs, which is natural and the lawn can withstand. In any case, use an insecticide labeled for grubs at the proper time of year.

• Weeds growing between cracks in brickwork or sidewalks are unsightly but easy to eliminate. Treat them with a nonselective herbicide when they are small to avoid having to pull them out by hand.

• If your hybrid roses have been losing their lower leaves and the remaining leaves have yellowish foliage with dark spots, then it is likely you have blackspot, which is a common fungal disease. Begin a spray program with approved fungicides immediately.

The fungicides need to be applied once every seven to 10 days as they work to prevent the disease and do not cure what is already infected. Be sure to clean up any leaves that have fallen from the plants. Many landscape shrub roses are resistant to blackspot so do not need to be on a spray program.

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