July gardening tips from Univ. of Missouri Extension

July 1, 2023 at 3:00 am KJFM Radio

KJFM NEWS — Garden Talk is produced monthly at the Adair County University of Missouri Extension Center in Kirksville, Mo.

July Tips and Tasks

Ornamentals
Provide water in the garden for the birds, especially during dry weather.
Remove infected leaves from roses. Pick up fallen leaves. Continue fungicidal sprays as needed.
While spraying roses with fungicides, mix extra and spray hardy phlox to prevent powdery mildew.
Newly planted trees and shrubs should continue to be watered thoroughly, once a week.
Fertilize container plants every 2 weeks with a water soluble solution.
Keep weeds from making seeds now. This will mean less weeding next year.
Keep deadheading spent annual flowers for continued bloom.
Perennials that have finished blooming should be deadheaded. Cut back the foliage some to encourage tidier appearance.
Plant zinnia seed by July 4th for late bloom in annual border.
Spray hollies for leaf miner control.
Prune climbing roses and rambler roses after bloom.
Apply final treatment for borers on hardwood trees.
Apply no fertilizers to trees and shrubs after July 4th. Fertilizing late may cause lush growth that is apt to winter kill.
Hot, dry weather is ideal for spider mite development. With spider mite damage, leaves may be speckled above and yellowed below. Evergreen needles appear dull gray-green to yellow or brown. Damage may be present even before webs are noticed.
Fall webworms begin nest building near the ends of branches of infested trees. Prune off webs. Spray with Bt if defoliation becomes severe.
Divide and reset oriental poppies after flowering as the foliage dies.
Semi-hardwood cuttings of spring flowering shrubs can be made now.
Summer pruning of shade trees can be done now.
Powdery mildew is unsightly on lilacs, but rarely harmful. Shrubs grown in full sun are less prone to this disease.
Divide bearded iris now.
Don’t pinch mums after mid-July or you may delay flowering.
Lawns
Water frequently enough to prevent wilting. Early morning irrigation allows turf to dry before nightfall and will reduce the chance of disease.
Monitor lawns for newly hatched white grubs. If damage is occurring, apply appropriate controls, following product label directions.
Vegetables
Blossom-end rot of tomato and peppers occurs when soil moisture is uneven. Water when soils begin to dry; maintain a 2-3 inch layer of mulch.
To minimize insect damage to squash and cucumber plants, try covering them with lightweight floating row covers. Remove covers once plants flower.
Dig potatoes when the tops die. Plant fall potatoes by the 15th.
For the fall garden, sow seeds of collards, kale, sweet corn and summer squash as earlier crops are harvested.
Set out broccoli, cabbage, and cauliflower transplants for the fall garden.
Sweet corn is ripe when the silks turn brown.
Keep cukes well watered. Drought conditions will cause bitter fruit.
Harvest onions and garlic when the tops turn brown.
Sow seeds of carrots, beets, turnips, and winter radish for fall harvest.
Cover grape clusters loosely with paper sacks to provide some protection from marauding birds.
Prune out and destroy old fruiting canes of raspberries after harvest is complete.
Blackberries are ripening now.
Apply second spray to trunks of peach trees for peach borers.
Early peach varieties ripen now.
Thornless blackberries ripen now.

July Pests and Problems

Continue to monitor for plant bugs on phlox and treat if required. Mildew is another common problem of phlox. Aster yellows is distinctive and can affect many different plants.