April

Lawns:

Now through July is the best time to plant such warm-season grasses as Bermuda grass, centipede and St Augustine.

Annuals:

Continue to enjoy the cool season annuals.  Deadhead winter plantings as need to prolong blooming.

Once the ground has warmed up (usually by Good Friday) you can seed summer annuals such as spider flowers, globe amaranth, cosmos and zinnias. 

Summer bedding annuals that tolerate our heat and humidity include moss rose, marigolds, annual dianthus, fan flower and ageratum. Impatiens, coleus and begonias are good in shade.

Perennials & Bulbs:

Apply pre-emergent herbicides to reduce spring-germinating weeds.

Perennial plants should be set out this month so they may become established before hot weather sets in. 

Plant warm-season bulbs such as caladiums, cannas, tuberoses, lilies, dahlias, elephant ears and gladioli towards the end of the month.

For better blooms this year, summer bulbs should be treated to a top dressing of fertilizer after new growth appears.

Trees & Shrubs:

Prune azaleas late in the month AFTER flowering. Never prune after July 4th.

Prune berry producing shrubs such a pyracantha, bur ford holly and other hollies will in flower to prevent removal of all the berries. Shape to desired form.

Fire blight is common on the new growth of pyracantha, pear and apple trees. Watch for this problem now and cut the infected foliage off. To prevent the spread of this disease, be sure to toss away the clippings.

Early this month, pruning is also in order for summer blooming beauties like crepe myrtle, buddleia and vitex.

Camellia and Azalea leaf gall is best controlled by handpicking the fleshy leaves or by spraying with zineb before bloom.

Roses

Spray roses every 7-10 days until frost, beginning with the onset of new growth.

Plant container-grown roses.

Control aphids with insecticidal soap.

Vegetables & Herbs

Lime takes its sweet time, so a light application now around newly planted tomatoes will help prevent blossom-end rot from occurring later.

This is the harvest season for cool-weather vegetables. Cut the broccoli while the buds are small and tight. Leave the plant in the garden after cutting the center head, as side shoots will develop for a smaller second harvest. 

Cut the lower leaves of Swiss chard, spinach, mustard, collards, kale and leaf lettuce. 

Prepare for Summer Heat

Plan for the intense heat and sun of upcoming months:
Mulch well. Cover soil around plants with 3 or 4 inches of organic material, such as wood chips, pine needles, or straw. Mulch also prevents weeds, which compete for water.

Water intelligently. Water infrequently (once a week  and deeply (three inches). Water early in the morning or late in the afternoon to reduce evaporation.

Use indicator plants. An Impatiens or two, for example, planted among flowers that demand less water will begin to droop and let you know that it's time to water the whole bed.

Protect plants from drying winds. Fences, latticework, building and larger plants and tree all provide attractive windbreaks.

Protect plants from sun. Trellises, pergolas, buildings, trees, and large shrubs all cast some shade.

Experiment with watering devices. Soaker hoses, drip irrigation systems and micro sprinklers will deliver water to your plants in a timely, efficient manner.

Use water-holding polymers in potted plants. Amend your soil in pots with these super absorbent crystals.