Watch for Diseases
Be on the watch for spotted leaves; whitish powder forming on foliage, stems, and buds; or triangular tan lesions on leaves. When possible, pick off individual leaves, but don't let them drop to the ground. Instead, put them in a paper bag and destroy them so diseases won't spread to other areas in your garden. Avoid working in the garden just after a rain, so you don't inadvertently spread disease.
Fertilize Lawns Carefully
If it's been over five weeks, fertilize the lawn with a slow-release lawn fertilizer that contains iron and sulfur. This will help the lawn turn from its pale yellow to green and help sparse lawns to thicken up. As lawn grasses thicken, this dense growth will crowd out the invasion of weeds. Avoid the use of weed and feed products that contain dicamba near and around the root zone of trees and shrubs.
Control Asparagus Beetles
Be on the lookout for asparagus beetles early in the morning. These reddish and black beetles can be found on the fern-like growth of asparagus plants. As they feed on the stems and foliage, the plant will grow distorted and become weakened. Reduced growth will deplete the plants of their strength and reduce production next season. Control the beetles by squishing them with your fingers or dropping them in a bucket of soapy water.
Use caution when pruning back your rhododendrons. Use sharp pruning shears and cut off the spent blossoms without cutting through the new growth that can be seen pushing its way into the faded flower. Lightly cultivate the soil around the bushes, and lightly fertilize with a slow-release, granular fertilizer (10-10-10). Lightly scratch the fertilizer granules into the soil and water in thoroughly.
Reduce Tomato Diseases
Prevent the invasion of potato psyllids that have migrated into the Rocky Mountain region. These tiny pests attack potatoes, tomatoes, and peppers. The tiny nymphs gather on the undersides of the leaves, and if not controlled, psyllids can severely damage the plants and reduce production. One of the safest controls is sulfur dust applied to the undersides of the foliage and along the stems.