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Almanac: July-August 2107

What To Do in the Garden in July & August


Mid-to-late July is the usual time for harvesting garlic. When about half the lower leaves are yellow or dry, pull the garlic and let it dry in a well-ventilated area out of direct sunlight for several weeks. Once dry remove the tops and place in a cool, dry location. Do not place the garlic in plastic bags.

From early July through August the raspberry cane borer is present and laying eggs in the tips of new raspberry canes. Upon hatching the larvae burrow down through the center pith, reaching the plant crown by fall. Affected canes often die. One cultural practice to reduce the damage is to cut off infested canes as soon as tips wilt several inches below the affected portion.

Renovate your June-bearing strawberries immediately after your last harvest for the season. Remove any weeds and then cut off the strawberry leaves. Apply five pounds of 10-10-10 fertilizer per one hundred linear feet of row. Narrow the row width to twelve inches by rototilling excess plants, mulch and weeds that are between the rows. Be sure to toss one half to one inch of soil over the remaining plants for better root growth. Immediately after renovation, irrigate the strawberry bed to promote new growth.

Be sure to put bird netting over your blueberries. The netting should go all the way down to the ground, otherwise birds will go up under the netting.

To control a number of diseases on tomatoes including late blight, monitor for symptoms especially if the conditions have been wet. Be ready to treat if necessary. Remember most fungicides are plant protectants and do not kill the disease once established. So do not wait to see the disease before starting your spray regimen. Multiple applications may be needed throughout the growing season. Read and follow label directions.

Keep an eye out for the imported cabbage butterfly larvae on your cabbage, broccoli, and other related crops. When noticed, handpick and remove caterpillars or use the insecticide Bt, as needed.

Try late plantings for fall harvest. Plant seeds of early cabbage, Chinese cabbage, broccoli, cauliflower, collards, kale, kohlrabi, Swiss chard, bok choy, beets, carrots, turnips, and rutabagas in the first half of July.

If squash vine borer has been a problem for you in the past, hopefully you took precautions in late June. If you didn’t, be watching the base and lower leaf stems for signs of an orangish-brown frass. As soon as you see this, slit the stem lengthwise with a knife, find the larvae, and destroy it. Next cover the slit vine with several inches of soil. If caught soon enough the plant will likely survive.

If your tomatoes have been growing well, but now some or all are wilting, you may have planted to close to a black walnut tree and are experiencing walnut wilt. These plants often die. Next year plant farther away from the walnut tree.

You may want to protect the developing apple fruit from apple maggot starting in late July with a home orchard fruit spray or use kaolin clay. Your other option is to place 3 to 4 red sphere sticky traps per semi-dwarf tree and replace each week starting the first of August through September.

Raspberries, blackberries, blueberries, elderberries, cherries, peaches, and other late summer fruit are susceptible to the relatively new invasive insect, spotted wing drosophila. This insect appears similar to other fruit flies but causes tremendous damage to the fruit, making the fruit inedible. Protective pesticide sprays containing the active ingredient spinosad provide very good protection. Start looking for this pest in July and throughout the rest of the growing season.

By late July petunias are getting straggly looking with a few blooms on the ends. Be selective and prune back these stragglers to two or three inches in height. It will take about four weeks before you once again have flowers and a more compact plant.

Most of the hybrid summer squash develop male flowers before the female flowers appear. Be patient as the female flowers and then the young fruit should start to appear within a week or two of the male flowers.

July through September is the time to divide and replant iris. Cut back the foliage to a height of six to eight inches for ease of handling. Dig the clump and separate into single or double fans. Be sure to label each fan so they do not get mixed up. Prepare the soil and replant being sure not to plant too deeply.

Do not bend onion tops. They will fall over on their own when they are mature. Bending the tops does not force the plant to bulb sooner. If your onions are not developing the size they should, you probably need to plant them earlier in the garden so they develop lots of leaves before they start to produce the bulb.

For best quality eggplant, harvest the fruit while young and immature. Unfortunately, there are no signs to help gardeners determine when to harvest eggplant other than size. If you cut into your eggplant and the seeds are brown, the fruit is past prime eating stage and you should harvest sooner.

Be sure to keep your mower blades sharp. You will have a better looking lawn, less disease, and your mower will be more efficient, saving you fuel.

Look over the bulb catalogs and place your order early.

If you need to renovate your lawn or reseed an area, August into September is the ideal time to do it. Be sure to have a soil nutrient test done on your soil several weeks in advance of seeding.

If you have planted any new trees or shrubs that have been planted in the past two years, be sure to water them during dry and droughty periods. Be sure to soak the soil ball area to a depth of ten to twelve inches.

Sit back on your patio or deck and enjoy your landscape and gardens. It doesn’t need to be all work.

—Russell Welser, horticulture educator, Cornell Cooperative Extension of Ontario County

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