Garlic mustard is a problem in native woodlands

Be sure to hand-pull garlic mustard that is flowering or setting seed now in your garden. This is an invasive biennial weed that is common in home gardens and a problem in native woodlands. A biennial plant completes its life cycle in two years.

Garlic mustard sends up a rosette of leaves in the first year and a taller plant with white flowers in its second year. Garlic mustard can be very small when it flowers. Some in my garden at home were about 5 inches tall and somewhat hidden by other plants.

It is best to dispose of the plant in your garbage, as most home compost piles do not generate enough heat to kill the seeds of this plant.

• Use a mulching mower that leaves grass clippings on the lawn. This means less work for you, and it recycles those extra nutrients back into your grass.

Regardless of which mower you choose, mow more frequently during spring to cope with rapid grass growth. Mulching mowers do not work well in tall, wet grass. Rake out any wet clumps of grass that remain on the lawn.

Keep the blades on your mower sharpened for a better cut. A good general rule to follow is to sharpen them after every eight hours of use.

Mow grass at 3 to 3½ inches in height, and frequently enough so no more than one-third of the total height is cut each time. I mow my lawn at a height of 3½ inches.

Most lawns are cut too short, which adds stress to the lawn. Maintaining lawns at a taller height promotes a strong root system and helps choke out weeds. In hot weather, short lawns can turn brown more quickly and weeds are more likely to move in.

• Many garden beds have irregular edges. Beds will look better and be easier to mow along if they have smooth, flowing curves.

Use a pliable garden hose or rope to lay out your new bed line. All clumps of grass should be removed from the bed and any clods of soil should be broken up and spread around.

Avoid the "volcano effect" around trees that is caused by piling soil and mulch up around the trunk, which then ends up looking like a volcano.

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