Fruits and Nuts:
Strawberries will benefit from an application of fertilizer in late August and again in September. Take a soil test to determine how much nitrogen, phosphorous and potassium is needed. Each is needed for strawberry production in varying amounts. Nitrogen is necessary to stimulate foliage and root growth while phosphorous is used to develop a good root system. Potassium has been shown to improve the color and soluble solids in the fruit.
Brown rot is a serious disease of stone fruits like peach, plums, and cherries. The disease is highly destructive and can ruin half or more of the fruit before harvest. Summers with much rainfall and high humidity lead to the greatest disease incidence. A fungicide treatment of Captan or Immunox is critical for control within one week of harvest. It is also important to remove all fruit from the ground where the fungus may overwinter. Remove any nearby Prunus spp., such as wild cherry, that may harbor this disease and serve as a source of infection.
Harvesting blueberries and other fruit can sometimes be challenging if the birds in your area are observant. Birds seem to know exactly when a blueberry is ready to pick and help themselves when the time is right. There are several methods you can use to protect fruits and vegetables from possible bird damage. Inexpensive netting can be used to cover plants and exclude birds. Try erecting fence posts with smooth wire on both sides of your blueberry shrubs and laying the netting over the top so that it covers the plants and can be staked to the ground. Frightening devices like plastic snakes, owls or the big eye balloons are a temporary solution. If left in one spot, birds quickly become accustomed to these and they will be ignored. To increase their effectiveness, move these devices around frequently. Bird cannons and distress broadcast systems are available with motion detectors that trigger when a bird enters the area. Since these devices do not operate until triggered, birds are more likely to be frightened and the device should be effective longer. One method being researched by Montana State University is the use of monofilament fishing line. In fruit trees, a pole is set next to the tree that extends two feet above its top. Lines are connected to the top and run to ground where they are staked. Space the stakes about 2 feet apart on the ground. For blueberries and brambles, use poles alongside the plants and run the line 2” above the crop and 12” apart. The spacing is such that birds could easily pass through between the lines but reasons are unclear why they do not. Some speculate that the monofilament line seems to appear and disappear confusing the birds to the uncertainty of a real barrier. It may also be that birds fear becoming entangled in the line. The monofilament line method works best on sparrows, but fails to repel robins and starlings. Research still continues on the use of this technique.
Groundcovers and Lawns:
Although, seeding can be done in the spring, conditions are best for sowing a cool season lawn in the fall (August 15‑ September 20). Cool temperatures and moist soils during fall promote plant growth and reduce the heat and drought stresses associated with spring seeding.
What about growing grass in the shade? Chances are you will not be successful at growing grass in heavy shade. Grass is a full sun plant and competition from trees for light and moisture often result in a thin lawn more susceptible to disease and less tolerant of heat, cold, and drought. Red fescue continues to be recommended as the best choice of all the cool season grasses for shade; however this species generally lacks heat tolerance and may die out in the summer. Overseeding annually may be required to maintain lawngrass density in shade. Seeding tall or red fescue under deciduous trees during late summer will provide the longest period of sunlight exposure. Of course, you could always consider vinca, hosta, or mulch beds as an alternative.
Perennial Flowers and Vines:
Roses will benefit from a final fertilizer application in mid-July. Apply fertilizer to rose beds at the rate of three pounds per 100 square feet. Spread the fertilizer around evenly and scratch it into the surface; then follow-up by watering the roses and the soil. Avoid fertilizing roses after mid-August. A late application may cause the roses to put on new growth which will be damaged by frosts.
Removing faded blossoms from perennials will prevent seed formation and possibly encourage more flowers to bloom late in the summer.
Trees and Shrubs:
Summer temperatures and drought can cause problems for newly planted trees. If you have a tree that has been planting during the last five years, it will require watering during the driest parts of summer to prevent excessive stress. Allow the water to penetrate the soil profile. Soaker hoses work well because they emit a small amount of water over a long period of time, allowing water to be absorbed instead of running off the surface. Applying mulch around the base of the tree can also help retain soil moisture. Avoid planting any new trees or shrubs this summer. Waiting until fall or winter, when temperatures are cooler and rainfall is more abundant, will increase the plant’s survival.
The Orange-striped Oakworm is an occasional pest in our area. Since it feeds late in the summer, it usually has little impact on trees. However problems can be severe on young trees just becoming established, where Oakworms may defoliate large areas. The Orange-striped Oakworm prefers white oaks but will feed on other oaks, maple, hickory, and birch. The caterpillars usually feed in groups and will skeletonize leaves leaving only the larger veins. The Orange-striped Oakworm is black with orange stripes, about 2 ½ inches long, and has two hornlike projections just behind the head. Larvae overwinter in the soil and the adult moths appear in early summer. A Bt product such as Dipel and Javelin implemented in mid to late July will help curb populations.
Yellow-necked caterpillars are active in early August. These caterpillars feed as a group, defoliating one branch at a time. They prefer birch and oak although they may attack crabapple, elm, basswood, willow and many other hardwood trees. The first leaves to be fed upon appear skeletonized and turn brown, often remaining on the tree. As the caterpillars grow they devour whole leaves. These brightly colored caterpillars have eight yellow longitudinal lines. The body is reddish brown when young and turns black as they mature. They are about 2 inches long when fully grown. Directly behind their black head, they have a yellowish-orange segment, which is where they get their name.
Vegetables and Herbs:
Several diseases have the potential to wreak havoc on your tomatoes this summer. Here are some of the more common ones and how to recognize and prevent them.
Fruit rots are caused by bacteria and fungi that enter an insect or mechanically damaged tomato plant. This generally occurs when temperatures are warm and humidity is high. Symptoms can vary according to the causal agent, but may occur as sunken lesions, water-soaked spots or scars. Avoiding injury when working around the plants, applying mulch to the soil to keep fruit from direct contact, and improving air movement by spacing plants or planting them in the direction of prevailing winds can help reduce disease pressure.
Tomato spotted wilt virus symptoms vary on tomato, but small, orangish-yellow flecks on older leaves are the first noticeable symptom. Later, new growth will be blighted and die. Fruit usually show characteristic green, yellow and red, slightly raised concentric rings. This virus is transmitted by thrips and has a wide host range including pepper where infected plants show light-green bud leaves and a black blighting of young growth. There are no effective controls for disease on either vegetable. Eliminate thrips or use resistant varieties.
Bacterial speck and bacterial spot can be suppressed by spraying plants with a fixed copper pesticide. This disease can appear on all the above ground parts of tomato plants as dark brown spots. Tank-mixing the copper with maneb or mancozeb improves the effectiveness of the copper and also provides early-blight control. Bluestone copper is not recommended since it will burn the plants. Avoiding overhead sprinkler irrigation can also reduce problems from this disease.
High temperatures can encourage outbreaks of two-spotted spider mites on beans, tomatoes and other garden crops. Watch for discolored plants and webbing and treat promptly with at least two sprays of Kelthane or malathion about 5 days apart.
If you are having trouble with raccoons, deer and rabbits in your vegetable garden fencing may be your most effective method of keeping these pests at bay. Small gardens do not require a lot of fencing. A two-strand electric fence (one wire at 6 inches and the other at 12 inches) will keep raccoons and groundhogs out of sweet corn and leafy vegetables. A chicken-wire fence two feet tall and tight to the ground will prevent rabbits from gaining access. For deer, try one strand of electric fence, 2 feet off the ground, with aluminum tabs attached every 3-5 feet. Smear peanut butter on these tabs which will attract the deer. When their nose or mouth touches the electric tab, they will learn to stay away. Many small animals can be trapped and removed. The secret in traps is the type of bait to use. Try sardines for raccoons, fruits for groundhogs and leafy vegetables for rabbits. If you have the space, you can grow a patch of ladino white and red clover to lessen garden feeding. Taste repellents are also available for deer and rabbits but are short lived and less effective.
A frequent question that comes up during vegetable garden growing season concerns plants such as cucumber, pumpkins, squash and zucchini that are dropping their blooms and not producing a fruit. The reason is really quite simple. These vegetables all belong to the Cucurbit family which produces both male and female flowers. Male flowers produce pollen rather than fruit and usually appear on the plant first. As female flowers emerge a few days later they are pollinated and will begin fruit set, male flowers having finished their purpose will then drop off the plant. To check your blooms for male or female, look below the bloom at the base of the flower. You should see a small fruit beginning to form on the female flowers. Anything that interferes with pollination may reduce fruit set and yield, including rainy weather or improper use of pesticides that may disturb bee activity.
July and August is a great time to start a fall vegetable garden. Some vegetables that do well in the fall include: bush and snap beans, broccoli, cabbage, cauliflower, collards, cucumbers, kale, kohlrabi, leaf lettuce, mustard, Irish potatoes, radish, spinach, summer squash, tomatoes and turnips.
Around the Home:
Birds need water just like us and during the drying heat of summer this can sometimes be hard to find. Help out our feathered friends by using water features in your garden. Birdbaths are simple and do an excellent job of providing a source of water and a way for birds to cool down. For best success with birdbaths, place them in the open away from shrubs and tall plants. This gives birds more security when ‘bathing’. Choosing a birdbath that has sloped sides will attract a greater variety of birds. Water gardens will also provide a drinking source for birds, but often the sides are too steep to allow birds access for bathing. Try putting a flat rock, which is slanted and partially covered with water, into the pond. This will give them easier access. Keep birdbath water clean and fresh by changing it every other day; this will also help prevent algae buildup.
You can make your own hummingbird feeder solution by mixing sugar in water at a 3:1 ratio. No dye is necessary, although red color on feeders or nearby plants may help attract hummingbirds. Change the solution when it starts to look cloudy. You can feed your hummingbirds through the summer without fear of keeping them from winter migration. The changes in day length and temperature is what triggers hummingbirds to migrate, not the availability of sugar solution.
Velvet ants, which are actually a type of solitary wingless wasp, cause a lot of confusion during the summer. People often think this insect is a fire ant. Their features however, confirm they are not. Although velvet ants resemble ants they lack the typical bump on the waist found on most ants. They are also covered in velvety orange or red hair with black stripes. This feature is often how the ‘fire ant’ label gets applied. You will not see velvet ants in groups, because they are a solitary insect. The larvae of velvet ants feed on ground-nesting bees, other wasps and some flies and beetles. The female is more often encountered than males and can be a concern to children. Their stinger is long and females can sting repeatedly. Most stings occur when people walk in an infested area barefooted. Chemical control is rarely needed. Telling children not to handle these insects and wearing proper footwear is often all that’s required.
Yellowjackets hurt. Just ask anyone that has been stung. They can be troublesome at picnics but downright dangerous when they nest near your home. This wasp lives in underground nests that have been constructed in hollow cavities. Yellowjackets are very aggressive and is why most people are stung while mowing the lawn. Other nesting sites include old tree stumps and rotted roots. Yellowjackets are more noticeable during summer because the colony has increased to its full size. Some nests can have as many as 5,000 wasps. To control this hazardous pest, locate the nest during the day. Return during the night when temperatures are cooler and yellowjackets are less active. Apply a drench treatment of insecticide, such as Sevin, to the entrance hole and then plug the hole with damp soil.