July Gardening Calendar
Published: June 19, 2019
- 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.
- 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.
- 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.
Gardening Calendar supplied by the staff of the William T. Kemper Center for Home Gardening located at the Missouri Botanical Garden in St. Louis, Missouri. (www.GardeningHelp.org)