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Summer Garden Challenges

Every season has its challenges, and summer is no exception. Some problems crop up regularly, but luckily you can take care of many of them with these simple tips.

Tree Complaints
Crape myrtles fail to bloom for several reasons, even in full sun sites that drain well. If you fertilize the lawn right up to the trunk, the tree may be getting too much nitrogen, which encourages it to produce leaves but not flowers. Remove the grass in a circle around the base of the tree and spread a 3-inch thick layer of mulch instead (but make sure mulch is not piled against the trunk). Then fertilize with a flowering tree formula fertilizer in spring and summer. Still no flowers? Trim 3 to 4 inches off the tip of each branch at midsummer. Winter pruning also can help to stimulate flowering the following summer.

Perhaps you've noticed a sticky mist falling from crape myrtles and river birches. This is honeydew, secreted by insects such as whiteflies, scale, and aphids as they are feeding on the tree by sucking out its sap. The honeydew falls on whatever is below -- leaves, furniture, your car -- and creates a perfect environment for black sooty mold to grow. That black film washes off, and insecticidal soap will usually control the insects, too, so you can stop this "rain."

Shrub Issues
Hydrangeas and other shallow-rooted shrubs can wilt on summer afternoons but recover by morning. Most often, the cause is a change in the sun exposure or problems with the soil. If you moved the plant last year, or if a tree that shaded it in the past has been cut down, an older shrub may not be able to adapt. Look around your neighborhood at the big mophead hydrangeas in bloom this month. The ones in full sun that do not wilt daily are in soil that drains well, and they are watered regularly. Full sun plus heavy soil or poor watering habits equals sad hydrangeas.

Solve this one by choosing semi-shaded locations and amending the soil with organic matter. And don't forget to water this and other shrubs, especially in summer, so the root zone is soaked, not just moistened.

Combo Pot Relief
Spring's sweet flower pots may be a bit tired soon. Cut back petunias and impatiens whenever they get leggy, then fertilize with a water-soluble formula to get them started again. Give up on the purely spring flowers and replace them with lanatana, portulaca, angelonia, Madagascar periwinkle, and other warmth-lovers. Summer's just getting going, and there's plenty of heat and sun to come.

Read more from The National Gardening Association