Northern & Central Midwest
Encourage Perennials To Rebloom
Some early-blooming perennials, such as catmint, delphiniums, salvia, geraniums, and centranthus, will produce a second bloom in late summer. Cut back the flower stalks or simply shear them as soon as they finish their spring bloom to encourage new flower buds.
Provide Mulch and Moisture for Tomatoes
Hot weather is coming and tomatoes will need an even supply of moisture to keep them from catfacing. These ugly brown spots on the blossom end of the fruit come from inadequate calcium uptake when the plant is soaked and then dries out. Deep straw mulch will moderate soil moisture.
Harvest Onions and Garlic When Ready
When onion tops fall over and garlic tops are about two-thirds browned, harvest the bulbs. Allow them to dry on the grass in the sun for two or three days and then move them to a dry spot where they will get plenty of circulation. Old screens make great drying racks.
Check Apple Maggot Numbers
Apple maggots lay their eggs in mid to late July. You can monitor numbers by hanging red decoy apples covered with a sticky coating in the trees. In small trees, these will work as the entire control. For larger trees, they will give you an idea of how many insects there are and how to time other control measures.
Clean Up After Oak Anthracnose
The cool wet spring in most of the Midwest has contributed to widespread oak anthracnose. Affecting primarily white and bur oaks, this fungal disease produces irregularly shaped spots and blotches that can deform the leaf and cause leaf drop. Clean up and dispose of any fallen leaves to prevent infection again next year.