Perennials, Shrubs, Trees
- Keep on top of weeding, especially the ones that have developed seeds, while carefully avoiding scattering the evil progeny.
- Water (especially anything planted this season) but water deeply, rather than frequently. Frequent, shallow watering will just encourage roots to stay at the surface, where they are vulnerable to heat and drought. Walk through your garden daily, if possible, to notice what plants might be needing a drink (and to spot and remove the worst of the weeds – the jungle-making vines).
- Chrysanthemums should be cut back by about half to encourage fall blooming (rather than later this month), and to create taller stems that don’t flop.
- Deadhead re-blooming perennials and annuals to encourage re-bloom, except for those with attractive or bird-supporting seed-heads, which you may want to leave in the garden until winter.
- Many shrubs will re-bloom if deadheaded, too – like many roses, spireas, and crapemyrtle.
- Remove dead, damaged or disease branches of shrubs and trees anytime. Same goes for suckers and water sprouts.
- July 4th is the traditional “last call” for pruning many shrubs that bloom next year on buds that are set this year (e.g., azaleas, rhododendrons, lilacs, early-blooming spireas). So if you want blooms next spring, do NOT prune these shrubs after the 4th.
- Except for roses, don’t feed your shrubs or trees now – wait until winter or early spring. But do give roses their final feeding of the summer this month.
- While fall is everyone’s favorite time to plant, it’s okay to plant in the summer if you keep the soil moist, especially in areas with some relief from afternoon sun and heat.
- Just keep on watering and feeding – all summer.
- Many annuals look better and have more blooms if their dead flowers are regularly removed.
- When it’s hot and dry – in July – cool season lawns usually become dormant. That’s normal and don’t worry – established lawns will quickly green up when it gets cooler and wetter. Newly seeded or newly sodded areas will still need watering.
- Remember to mow cool season grasses at the 3 to 3 ½ inch height or as high as your mower will cut. This helps to retain moisture and cool the roots of these grasses. (Warm season grass like Zoysia is cut at the 2 inch height and will be green throughout the summer.)
- Leave grass clippings on your lawn to provide Nitrogen to the soil.
- According to the University of Maryland, now is the time to fertilize Bermuda grass and zoysia grass – apply according to the instructions on the bag. Do not fertilize cool-season grasses (i.e. fescues and bluegrass) until fall.
- Now is a good time to add water lilies to your pond. With warm water and long days, the lilies are starting to bloom.
- Also, be careful with water hyacinths and water lettuce. These floating plants are added to filter the water and keep it clear, but they reproduce rapidly and will totally cover the surface of the pond by the end of summer. Even very large ponds. Make sure to pull out the extras as summer goes by; they are good added to the compost pile. These plants are serious invasive weed problems in the South. They won’t overwinter here, but you must remove them in the fall so that they don’t decay in the pond after they die.
Pests in Ornamental Plants
- Be alert for slug and snail damage. They’ll hide during the heat of the day, then come out of hiding in the cool mornings and evening hours or after a rain. Seek and destroy all slugs and their eggs! Use Sluggo for best control.
- Many different kinds of caterpillars are feeding on shade trees. No controls are necessary unless severe defoliation is observed.
- Be on the look-out for Japanese Beetles, which make your plants look chewed-up. Plants most affected by the beetles are roses, perennial hibiscus, and fruit trees. What to use for control? Permethrin, or Neem oil.
- Never apply any pesticide to a dry or stressed plant, even if the pesticide is an oil or insecticidal soap. Also, never spray in the heat of the day – wait till after dinner.
- Grab your hose and really go after your Dwarf Alberta Spruce – vigorously spray the plant to knock off the spider mites. How to tell if your spruce has spider mites? Simply place a piece of white paper under a clump of foliage and rustle the branch allowing debris fall on the paper. Then look very closely for signs of moving critters.
- Keep on top of weeding and watering.
- Keep feeding your summer vegetables, too.
- Keep feeding fruit trees and shrubs (except for figs, which shouldn’t be fed while fruiting). Hollytone is recommended for blueberries, Rosetone for non-acid-loving plants like cherry trees.
- Soil pH -changes could be applied between now and fall. That means lime on fig and cherry, sulfur on blueberries (they do well with strong acidity).
- A late crops of beans, beets, carrots, Swiss chard, and cucumbers can be direct sown through the end of July.
Pests in Edibles
- Squash vine borers are hatching out and boring into squash and pumpkin vines. Monitor plants for signs of wilting and entrance holes on lower stems. The easiest and surest method of control is to cut a slit in the stem above the hole with a razor, remove the 1 inch long brown headed white larva. Mound up soil around the wound.
- Blossom-end rot of tomato, pepper, squash and watermelon may be observed now. Remove fruits that have blossom-end rot or are badly malformed. This nutritional disorder is caused by a lack of calcium in developing fruits and is brought on by dry conditions. Water your plants deeply and regularly and keep them mulched. Tomato plants may need 1-2 gallons of water each at least twice a week during drought periods.
- Remember to change the water in the bird baths regularly, and keep them filled. Standing water is a breeding ground for mosquito larvae.