Tasks & Tips for July
Here’s the ornamental garderner’s To Do List for July:
- Deadheading and pruning can yield more flowers on certain perennials. Shear or pinch back the spent blossoms of lavender, scabiosa, snapdragons, garden phlox, purple coneflower, and thread-leaf coreopsis so that the plant will develop more blooms later on. If you want to know more about deadheading and pruning, I highly recommend the book The Well-Tended Perennial Garden by Tracy DiSabato-Aust, whose studies in her own garden have made her an expert.
- Pinch back chrysanthemums and asters one last time no later than mid-July. Do not pinch them back after that. Otherwise, the plant will not have time to set buds for this growing season. Pinching these plants back helps keep them from splaying open in the middle and also delays bloom time until later in the growing season.
- Water new plantings to be sure they stay moist.
- Water plants in the cooler, early morning hours so that the water will soak into the ground rather than evaporate into the air.
- Water plants deeply, giving them about an inch of water per week.
- Avoid sprinkling plants from overhead. That just moistens the top of the soil but it doesn’t put water down at the root level where it’s needed.
- Use drip irrigation or soaker hoses under the mulch to water slowly and deeply at the base of each plant. If you don’t have drip irrigation, use a hose with an adjustable nozzle or a watering can to deliver water only at the base of each plant. Don’t water the foliage.
- Mulch. If a drought develops, add more mulch. Use a 2- to 3-inch layer of mulch to help hold moisture in the soil and to help protect plant roots from the summer heat.
- Weed before those weeds set seed and before they steal nutrients from your desirable plants
- Postpone new plantings until the cooler days of September
What’s wrong with my dogwood’s leaves? If the leaves on your dogwood are turning reddish, it might have powdery mildew. That’s right, on a dogwood, powdery mildew doesn’t look gray; instead, its leaves look like they’re prematurely turning to their autumn colors. I learned this from a video recently produced by the Va. Cooperative Extension Service, https://www.youtube.com/watch?v=JFH92cxuYKk.
What’s wrong with my boxwood? That question haunted me for a few weeks last month when spots appeared on some of my boxwoods. Then I sent samples to the lab at Virginia Tech. Was it boxwood blight? No, it was a boxwood leaf miner. What a relief! We are lucky to have the assistance of the specialists at Va. Tech. Samples should be brought to the Extension Office on 5th Street Extended. Master Gardeners will help you prepare your samples and send them off to the Va. Tech lab. Also, if you’re wondering if you have boxwood leaf miners or mites, take a look at this publication, “Insect and Mite Pests of Boxwood,” https://www.pubs.ext.vt.edu/content/dam/pubs_ext_vt_edu/ENTO/ENTO-42/ENTO-312.pdf. Stay on the alert for boxwood blight. When in doubt, get it checked out. The Virginia Extension Office has a new series of videos on boxwood blight. https://www.youtube.com/watch?v=6wENgjHYumc
If you’re using rain barrells or stock tanks to store rainwater — an earth-friendly practice — be sure to treat that standing water to prevent mosquitos. The larvicide in mosquito dunks or rings is a naturally-occurring bacteria from the soil and does no harm to wildlife, except to mosquito larvae. Read more about backyard mosquito control in “Battling Mosquitos,” N.C.Ext.,https://chatham.ces.ncsu.edu/2014/08/battling-mosquitoes-2/.
Speaking of rainwater, if your yard was subject to runoff problems during last summer’s heavy rains, you might wish to check out a new series of publications called “Stormwater Management for Homeowners,” https://www.pubs.ext.vt.edu/SPES/SPES-9/SPES-9.html. You’ll learn about various practices, like rooftop redirection, rain barrels, permeable pavement, grass swales, rain gardens, and buffers that allow you to manage runoff at the source, thus preventing large volumes of polluted runoff from going into storm drains that flow directly into nearby streams, rivers and lakes.
July is often the peak month of bloom in many gardens, so be sure to stop and enjoy those flowers.