Look closely to determine what’s ailing your plant

Summer is officially here, and with it a host of problems in our gardens.

We want to save our plants when something goes wrong, but to solve a problem, we first have to determine what it is. The following system should help you identify the problem and find a solution.

Step 1 is to identify the plant so you know what is normal for it.

Yellow leaves can be a sign of nitrogen deficiency, or heat stress, but many plants are supposed to have them. Applying fertilizer might solve the nitrogen deficiency but could burn the plant if that’s not the problem.

For a good identification, take a cutting to your favorite nursery or the Master Gardener plant clinic.

Next, examine the entire plant and other plants nearby. Write down everything out of the ordinary, even if it seems unrelated, because it could be a clue.

Is the damage uniform, perhaps affecting just one side of the plant, or the whole plant evenly? Is it uneven damage, appearing randomly on the plant? If the damage appears uniform and doesn’t progress, or if the same symptom appears on different species of plants, the cause is usually human related, from cultural or mechanical events.

A random pattern that gets worse, or is confined to one type of plant, often has a cause like animals or disease.

More than half of all problems are cultural or those related to growing conditions. Check the soil to see if it’s moist enough, and research the plant’s needs to determine if it’s receiving enough light, air circulation and nutrition.

Make sure the plant is cold and heat tolerant for our area.

Have there been fertilizer or pesticide applications that could have caused this problem? Could there be a nutrient deficiency?

Mechanical damage often occurs from some outside force such as bark damaged by weed trimmers or lawn mowers hitting trunks. The symptoms caused by mechanical damage are often very similar to those resulting from cultural, disease or insect problems.

Animals, including insects, cause physical damage, like chewed leaves or holes in the trunk. They leave signs like eggs, webbing, or frass. If you walk through the garden in the evening, looking under leaves, you may even catch them in the act.

Diseases, including fungi, bacteria and viruses, very often start with leaf spots. As they progress, they can kill the leaf, cause twig dieback or kill the whole plant.

Sunken areas of plant tissue, or mushroomlike structures growing out of the plant, are indicators of disease. If you suspect this type of problem, it’s best to consult an expert. She will need to see a sample of the plant, including both healthy and unhealthy leaves and/or stems.

The same symptom can have several possible causes, so be thorough in your investigation and consult the experts. You can bring plant samples to the WSU Spokane County Master Gardener plant clinic, 222 N. Havana St., or your favorite nursery. For an on-site consultation, talk to a certified arborist or another landscape professional.

With a little work you can find a solution.

This week in the garden

We’re heading into the hot and dry part of the season, so keep your plants healthy by giving them plenty of water. Remember to deep-water trees and shrubs and watch for any signs of drought stress.

Raise the mowing height on your lawn to protect it from the heat of July.

Fertilize your June-bearing strawberries after harvest.

Keep your garden weed free now, to prevent the weeds from producing seeds for next year.

Keep your annuals blooming by cutting off the spent flowers.

If you have a birdbath, remember to change the water frequently, and clean it regularly to prevent disease.

Lastly, take a daily stroll through your garden. Take in the scent of all the blooming plants. Pull a few weeds.

Winter will be here soon enough.