Thin or compacted turf will benefit from core aeration and over-seeding. Keep new seed moist until germination.
Remove spent blooms on tulips, daffodils and other spring flowering bulbs to focus its energy on growing new bulbs rather than producing seeds.
Plant tomatoes, peppers and melons after the danger of frost is past and the soil temperature is 65° F – usually around the last week in May. Rotate plants each year to reduce insect and disease problems.
Ground covers such as vinca, ajuga, pachysandra, creeping foamflowers, lamium, and ivy can be divided, transplanted and fertilized now.
Start to monitor lilies for red lily leaf beetles. Check the underside of leaves for the clusters of tiny orange eggs and remove. Spray with Neem every 5-7 days to kill larvae and adults or handpick and destroy.
Plant dahlias, gladioli, cannas and other summer flowering bulbs. Put hoops and stakes in place for floppy plants.
Turn your compost pile to add oxygen and speed decomposition.
Feed azaleas, rhododendrons, and other ericaceous ornamentals with fertilizers for acid-loving plants.
Begin deadheading roses and apply fertilizer in mid-May, mid-June and mid-July.
Fill hanging baskets and containers with trumpet-shaped blooms such as nasturtiums, nicotania, fuschias, and salvias to attract hummingbirds.