July Horticultural Tasks
By Amy Wright
Annuals
If you used a slow release fertilizer in the spring to fertilizer your annuals, now is the time to reapply. They have a four month life span, so this application will take you through the remainder of the growing season. Pay close attention to the water needs of plants in containers as they will dry out faster than will plants in the ground. If you find that your potting soil doesn’t seem to hold water like it used to, it may be time to get new potting soil. Potting soil is not meant to last forever, but for about two years. If you want to wait until fall to make the change to new potting soil, this trick will help you get through until then. Add just a couple of drops of dishwashing detergent to your watering can before watering your containers. The detergent will add a cohesive action to your potting soil so it won’t dry out so quickly. Many annuals will need to be dead headed to keep them blooming. Pinch back coleus and impatiens to keep them from becoming too leggy.
Turf
This is not the time to try to establish a new turf area. Watch for damage from mole crickets, beetles, and chinch bugs. Be sure to vary mowing patterns and keep grass cut a little higher now because of the heat. Check irrigation for need of repairs or to make sure heads haven’t been misaligned and that you’re still getting the coverage needed. Dry spots in a lawn will quickly lead to dead areas.
Perennials
Reapply slow release fertilizers to perennial plants now, too. If you have perennials that have already finished blooming, you can often get a second bloom period out of them by dead heading them now. This will cause them to bloom again during the late summer. Keep an eye on aphids, spider mites, and other heat loving insects during this month. Treat with a systemic insecticide for best results.
Roses
Do not fertilize roses this month. However, if you have Knockout Roses, they can be cut back 1/3 to encourage new growth and set an intense display of blooms. Japanese beetles can be a nuisance on many plants including roses at this time of year. There’s an easy way to take of them. Take a jar of soapy water (dish soap will do) out to the plants that Japanese beetles are feeding on. Hold the jar beneath the beetles and tap gently on the plant. The beetles will react by dropping off the plants and fall into your waiting jar of soapy water where they will die. This can be done a couple of times a day for the short time that Japanese beetles are feeding on your plants.
Shrubs
Little or nothing should be done to shrubs now. It’s a good time to note which shrubs may be needed to be replaced in the fall when planting times comes around again. Many conifer type shrubs are susceptible to spider mites during hot, dry summer months, in particular Dwarf Alberta Spruce. These can not easily been seen until they’ve cause irreparable damage. Monitor closely for webbing or discoloration of plants. Treat with a miticide that is labeled as safe to use on the plants affected.
Trees
Enjoy and appreciate the shade that trees provide during our summers. If you have an area that gets too much sun for your liking, start thinking now about where a tree could strategically planted in the winter to cast shade to cool your house and yard.