Western Mountains and High Plains
Clean Up Around Tree Trunks
Remove grass and weeds from around the trunks of trees. Lawn mower nicks on the lower bark is a leading cause of stress that leads to disease and susceptibility to insect attacks. Problems with this "lawn moweritis" can be avoided if the grass is removed in a circle at least three feet from around the trunks.
Don't Fret About Leaf-Mining Insects
Be on the watch for a group of fascinating insects that can be observed tunneling in birch, aspen, and poplar leaves. Leafminers can cause different-sized blotches in the leaves that make the leaf appear papery or translucent. Except in situations of heavy infestations, leafminers do not cause serious damage nor do they threaten the health of the trees. If you are concerned about the cosmetic nuisance on the plants, carefully pick off the infested leaves.
Feed Container Gardens with Organic Fertilizer
Fertilize hanging baskets and container gardens on the patio or deck with a slow-release organic flower fertilizer. This is the lazy gardener's way: "Feed " the plants once and the fertilizer will release nutrients for the rest of the growing season. Sprinkle the fertilizer granules on the surface of the soil and lightly work in with a hand trowel or cultivator. Each time you water, nutrients are made available to the plants as they need them.
Keep Rose Diseases at Bay
Check your rose bushes for evidence of diseases including leaf spot, mildew, and rust. The symptoms of black spot, as its name implies, are circular black spots that are often accompanied yellowing. The condition will often develop on the lower foliage and spread upward. Powdery mildew is a coating of gray-white powder on the leaves. Rust will appear as reddish-orange pustules on the undersides of the leaves. Hand-pick of diseased leaves and dispose or select an organic fungicide to apply as a preventive.
Cope with Fireblight
If you observe bacterial disease on some of your crabapples, mountain ash, pears, and apples, don't be in a hurry to prune it out as is often suggested. Plant pathologists are finding that the infection on the tip or terminal portions of the plant will almost always stop just at the juncture with the twig. Later the "tip-blight" will fall off. This will also reduce spread of the disease to pruned and exposed lesions.