Summer flowers can now be planted; plant summer bulbs such as cannas, dahlias, and gladiolus.
Pinch back growth of newly planted annuals and perennials; this will help the plants develop more flowers.
You can prolong the flowering season for your spring annuals by cutting off the old blossoms.
Cool-season vegetables will quickly decrease in quality once the weather gets hot. Be sure to harvest these vegetables and then replace them with warm-season vegetables such as okra and sweet potatoes.
Apply mulch around heat sensitive plants to keep the roots cool and to prevent water evaporation.
Put shade cloth over tomatoes.
Be aware of insects. Many bugs appear in May, including lace bugs, aphids, and bagworms.
Fertilize both cool-season and warm-season lawns.
Seed Bermuda and warm-season grasses as soon as the soil warms up. Apply 1 inch of water per week.
Once every 2 or 3 years, dethatch Bermuda lawns during their active growing season (May through August).
Continue fertilization of your rose bushes; liquid fertilizers can be added every two weeks.
Take care to keep deciduous fruit trees well-watered this month. Do not prune.
Cover fruit trees with netting to protect the fruit from bird damage.