Blog Post

This summer certainly has been tough on the landscape. Strings of 90-degree heat, low humidity and the lack of reliable precipitation have taken their toll on plants and gardeners alike.

Even though we may want instant results, it takes time and patience to solve some of summer’s lawn and garden problems. The most important step in the problem-solving process is to diagnose the problem correctly. An incorrect diagnosis can lead to even more problems.

For example, many lawn issues can look similar, but have different causes. That patch of dead grass on the front lawn could be caused by a lack of water, insect damage, a fungus or a dog spot.

If you’re seeing problems in your bluegrass lawn right now, it might be a fungus called summer patch. Sometimes summer patch starts as small circles of dead grass or larger patches that seem to appear overnight.

This plant fungus takes over turfgrass roots when there are extended periods of hot temperatures following wet weather. Sound familiar?

Because summer patch is a root disease, solving this problem means using good lawn practices to encourage healthier roots. One method is to raise the mower height to leave grass blades taller. Aeration to improve drainage may also help.

But lawns that look like they have summer patch might have necrotic ring spot instead. Both show up in the same way in lawns and the only way to know for sure is to have a turfgrass sample evaluated.

You can take a sample to one of the lawn and garden experts at Nick’s or you can contact your county’s Extension office to ask about plant diagnostics. The key to a good diagnosis of the problem is a fresh sample. Once the sample has died or is dry, it’s almost impossible to distinguish one problem from another.

For lawn samples you’ll need a large sample (about the size of a shoebox) that shows the transition from the healthy grass to the affected area. It’s important to keep the roots covered and take the sample in quickly before it dies or dries.

For samples of trees and shrubs, it’s best to take a sample of a branch that’s at least 12 inches long and that has leaves attached. Again, the sample should show both healthy and affected leaves.

Weeds are also easier to identify if you bring in as many fresh plant parts as you can collect.

A good diagnosis takes the guesswork out of solving the problem. Once you know the reason for the plant problem, you’ll be able to discuss the options for controlling it.

Gardeners start the season with such high hopes for growing bushels of beautiful tomatoes. Then August hits and we’re reminded that tomatoes can sometimes be challenging to grow.

Often the problem is obvious, like when a hungry squirrel eats half a ripe tomato right off the vine. Other times, the problems come from plant diseases or insect pests.

Here are some common tomato problems for this time of year, and what to do about them:

Plants are wilting. Sometimes wilting is because plants need water and other times it’s because tomatoes are being overwatered. Before watering plants, be sure to check to make sure the first inch or two of soil is dry. If plants start to wilt in the middle of the day, even when the soil is moist, the problem may be a soil-borne fungal disease like verticillium wilt or fusarium wilt. Pull up plants that don’t recover and dispose of them in the trash.

Damage on tomatoes. When you see problems starting on the tomatoes, pick those fruits and toss them on the compost pile. There’s no reason to leave wormy fruit or tomatoes with blossom end rot on the plant because it takes energy away from forming other tomatoes.

Soil dries too quickly. Mulch around each plant (even in containers) with an organic mulch like thin layers of dry, untreated grass clippings, dried tree leaves, or straw. Water plants deeply, but infrequently.

Blossoms are dropping. When daytime temperatures heat up too quickly and nighttime temperatures remain high, tomato plants can drop their flowers. There’s not much you can do except to wait for cooler nighttime temperatures.

Spots on leaves. Spots could be caused by a fungus, most likely late blight at this point in the summer. Look for problem leaves growing on the upper part of plants that shrivel and die. In the future, space plants farther apart to help with air circulation and be sure to water at soil level to keep leaves dry.

Leaves disappear overnight. Look for tomato hornworms, those large green caterpillars that eat the leaves off plants. These insects are difficult to see because they’re the same color as the plants. Look closely, pick them off by hand and drop them into a paper bag or bucket of soapy water.

Leaves that yellow and curl. The problem could be psyllids, tiny insects that also feed on plants. Pick off the unhealthy leaves and throw them away, and then look on the undersides of healthy leaves. Hose off the insects with a blast of water early in the day so leaves have time to dry.

Tomatoes with cracks. Cracks that appear as circles at the stem end of the tomatoes or along the side are the result of rapid growth. This problem is usually caused by wet weather followed by dry weather. Use mulch and be sure to keep the soil deeply and evenly moist.

Leaves turn yellow and drop. Spider mites may be the culprit. Infestations of these pests show up as small specks on leaves. Look for these small red mites on the underside of leaves and hose them off with water. Keep checking to make sure they don’t return.

Tomatoes aren’t ripening. Root pruning may help speed up the ripening process. Remove any tomato blossoms that form in late August (they probably won’t have time to mature), stop fertilizing plants to slow growth, then use a shovel or hand trowel to cut through the roots around the plant, about 8 inches from the stem. Leave the soil in place. Pruning tells the plant to get busy ripening the fruit because the end of the season is near.

August seems like the time when some gardeners start to let gardening tasks slip. But don’t give up yet! There’s still time to get out and enjoy the garden while summer is in full swing. Keep pulling those weeds and watering those plants. If your landscape is starting to look a little droopy, perk it up with some new plantings.

Here’s what you can do in the garden this month:

Remember to plant biennials. Biennial plants, like hollyhocks, can be planted now so they have time to start growing and set good roots before the ground freezes. They’ll start regrowing next spring, ready to bloom.

Search for shrubs. Take a walk around your yard and look for places that could use a new shrub or two. If you want to see your landscape in a new way, set your camera to black and white to take a few photos. By taking the color out of the picture, you’ll be able to see blank spots or what plant sizes and shapes are missing from the landscape.

Plan for perennials. Look for hardy perennials that will bloom next season. Planting them now gives roots time to start growing through fall. Then next year they’ll be ready to start growing again.

Add new annuals. Sometimes annual plantings can be refreshed by cutting stems back and fertilizing. While you’re waiting for the next flush of flowers, buy a few new annuals for instant color.

Pull out spindly plants in containers and window boxes. Replant containers with a few fresh plants for a new look. One of the easiest ways to do this is to make room in the soil for the plant and its container. As the seasons change, it’s simple to remove the container and pop something new in its place.

Continue planting cool-season vegetables for fall harvesting. Good choices to plant in August include beets, kale, lettuces, mustard greens, radishes, spinach and turnip greens. Save growing time by planting some vegetables from transplants instead of seeds.

Plant more herbs. Arugula, chives, cilantro, dill and parsley all make for a second season of summer harvesting. Look for transplants or seeds that will sprout and grow in the shortest number of days.

It’s not often I resort to a toxic chemical to get rid of insect pests in my garden. But when hollyhock weevils showed up again this year, I knew I had to take some drastic action.

These weevils not only eat big gaping holes in the plant’s leaves, they use their long beaks for chewing into the flower buds so they can lay their eggs. Then the grubs feed on the seeds which can spell the end to having hollyhocks in the future.

Last year I spent many summer mornings picking these destructive pests off the plants and crushing them with my fingers. Damaged pods had to go, too.

So at the first sign of weevil damage this season, I decided to bring out the heavy artillery. I spent a lot of time researching pesticides before finding one that would take care of the weevils, but wouldn’t kill beneficial insects, too.

When using pesticides, it’s important to keep pollinators in mind. Bees are especially vulnerable to pesticides, and they need our help to keep their environment (and ours) safe and healthy.

Maintaining a healthy garden is the best way to avoid using pesticides in the first place. Start with clean soil, use adequate amounts of water without overwatering, and destroy unhealthy plants. At the end of the season, clean up garden debris so pests can’t overwinter.

Be observant in the garden and take action as soon as you spot a problem and before it can get worse. Some insect problems can be solved with several days of strong blasts of water from the garden hose.

Another organic method to get rid of insect pests is handpicking them off of plants and dropping them into a paper bag, trapping them with sticky traps or dishes of beer (or yeast-water mixture), or laying out boards for them to hide under at night and removing them the next day.

If pest problems persist, use the least toxic chemicals first, like neem oil, insecticidal soaps and repellants.

When you do decide to use a toxic pesticide, be thoughtful about it. Remember that fewer than 10 percent of insect pests warrant the use of pesticides. Decide if the plant damage is significant enough to call for using a pesticide in the garden.

Don’t grab the first pesticide you see. Read the label carefully to make sure it will treat the insect you’re after without causing harm to other insects or animals.

Follow all label directions precisely and wear the correct safety gear when applying. Use the right amount to spot treat the problem. Avoid indiscriminate spraying of all plants to solve one pest problem.

If spraying, do so at night when bees and other pollinators aren’t active in the garden. And when you’re done, store or dispose of containers properly.

Another method for dealing with insect pests is to take a wait-and-see approach. If you wait before using toxic chemicals, you’ll often see the problem isn’t as bad as you first thought.

Want to cool off in the garden this summer? Then plant a shade garden. It’s easy to create a shady retreat under tall trees, next to the shady side of the house and garage or to plant a small garden in an underused space.

Some gardeners shun the shade because they think it’s too challenging to plant where the sun doesn’t shine. But there are plenty of opportunities to plant a green and growing garden in the shade. Shade gardening is all about foliage color, shape, size, and texture.

The key to gardening in shade is to carefully match the plants to the site and to each other. A simple combination of hosta plants in different sizes mixed together with colorful impatiens will add depth and color to just about any shady spot.

For a fun take on a kitchen garden, look for plants that are named after favorite foods. Hostas are especially appetizing in a shade garden when they have names like ‘Java’, ‘Cookie Crumbs’, ‘Peanut’ and ‘Squash Casserole’.

Impatiens typically perform well in partial shade with early morning or late afternoon sun. Good colors for shade include deep pink, salmon and violet.

The colorful foliage of coleus plants can add striking texture to the shade garden. New varieties feature bright and novel colors, like burgundy tinged green leaves or multicolored plants with finely textured foliage.

Another simple way to start planting in shade is to plant in different sizes of containers. Mix or match the container materials for added interest and then fill them with an assortment of shade-loving plants. Tall ornamental grasses, daylilies and tuberous begonias all work well together in shade.

In deep shade gardens, fountains, bird baths, statues, urns and tall obelisks add structure and can take up large spaces. If there’s room in your shade garden, a garden bench or table and chairs makes for a cool seating area.

Use groundcovers to provide the finishing touch. Vinca can act as a green carpet with shiny, dense foliage and small lavender or blue flowers. Dead nettle is another groundcover that adds texture to the shade garden with silvery foliage and small flowers.

What else would you add to your shade garden to make it a perfect place to relax this summer?

So many insect pests, so little time to crush, drown and destroy them.

July seems to be when insect pests start to show up and cause damage to garden plants. Some damage is simply cosmetic, like holes in leaves, but other insect damage can cause plants to wither and die.

To keep your landscape and garden healthy, spend a little extra time looking for these insects and then take action to control them:

Aphids are small pear-shaped insects that suck sap from plant leaves making them curl. If you see aphids (or groups of ants attracted to aphid infestations) dislodge with a strong stream of water from the hose every few days until they’re gone. Insecticidal soap also works to rid plants of aphids.

Cabbage worms start as little white butterflies that lay eggs. The eggs grow into cabbage caterpillars that attack cabbage leaves. If the eggs are hatching, look for the fat caterpillars under cabbage leaves. Pick by hand and drown in a bucket of soapy water. Bt (Bacillus thuringiensis) is a soil bacterium that helps control caterpillars. Apply Bt by shaking the dust over plants.

Flea beetles are tiny insects that eat small holes in leaves. In early spring, row cover cloth can protect young plants, but later in the season white sticky traps do a better job.

Slugs typically show up when conditions are too moist. Check for slugs at night when they’re feeding or look for them early in the morning. Keep soils on the dry side to prevent slugs. Traps of yeast water (or beer) will attract and drown them. Diatomaceous earth sprinkled around plants will also discourage slugs.

Spider mites leave a fine webbing on plants and some speckling on the undersides of leaves. A strong blast of water from the hose can knock them down. Insecticidal soap can also be effective.

Tomato hornworms are large green caterpillars that feed on tomato plants and can strip a plant’s leaves in a day. Take your time to spot these pests because they’re the same color as leaves and stems. Handpick or knock them into a bucket of soapy water or a paper bag for disposal.

Keep checking your vegetable garden, flowering plants, shrubs and trees for signs of insect damage throughout the summer. The sooner you spot a problem, the sooner you can take action to maintain a healthy landscape.