Some common ailments afflicting your plants
We would be happy to diagnose your plant problem. Make sure you bring in a sample with the condition on it. We have many products available to help cure your plants problem. However, if you would like to get a jump start, here is some expert advice on common ailments for you to go by.
Diagnosing plant problems requires careful observation of your plants in their environment. Knowing how to look for clues to a problem and what types of clues to look for is half the battle.
Begin your diagnosis with learning how to observe. Note the plants general condition. Is the entire plant affected or just a part such as, just the branches or just the leaves. Look for patterns in its relationship to other plants around it. Most causes are found on the trunk, on the roots or in the soil. Using a magnifying glass may help you see details that are not easily detectible. Insect problems are not always apparent.
If the initial inspection does not show any obvious reason for symptoms, observe other factors such as recent weather conditions, the past winter conditions, or an unusually dry or wet summer. Have you fertilized lately, or how did you prune. Is your plant buried to deep? You may have to dig into the plant or soil to find the cause. Look under leaves or slice into a piece of bark on a wilting branch to see if the wood is healthy.
Many times, the root cause is in, well, the roots. The key to a root problem is often in the soil. You can purchase a pH test kit from us to test soil conditions. Also, you may have to dig around a part of the roots to detect any problems with insects or other soil issues.
Many problems affect plants at certain times of the year. For instance, Rust is usually a spring and early summer problem for snapdragons and roses, when the weather is warmer but still moist.
After diagnosis, administering a cure is the next step. At this point, many books exist on how to cure plant diseases using the "better living through chemistry" principles or more organically, such as using beneficial bugs. Again, we would be happy to help you out. Just bring in that sample.
Below are several common plant ailments that we see all the time on customer's plant specimens during the season:
Leafminers: Green or whitish translucent winding trails, blisters, or blotches develop on leaves. The trails, blisters, or blotches later turn brown. If an infested leaf is torn open, several small green, yellowish, or whitish insect may be found inside the leaf.
Leafminers are the larvae of flies, moths, beetles or sawflies that hatch and then have your plant for dinner. We especially see them affecting Birch. Unfortunately, Leafminers are hard to control because the larvae is protected inside the leaf and most insecticides are for eradicating adults. Check your foliage periodically to see when the hatching occurs then come in to our nursery and ask our experts which insect control would work best for your plant variety.
Black Spot: A big one for roses, especially in our marine climate, but this fungus can affect other plants as well. Circular black spots with fringed margins appear on the upper surfaces of the leaves in the spring. The tissue around the spots or the entire leaf may turn yellow, and the infected leaves may drop prematurely. Plants may loose their leaves by midsummer, flower production is often reduced and flower quality is poor.
Black spot is Caused by a fungus (Diplocarpon rosae) that is a severe problem where rain is common in the spring and summer. The fungus spends the winter on infected leaves and canes. The spores are spread from plant to plant by splashing water and rain. Twigs may also be infected and plants are often killed by repeated infections.
At the Plant Farm, we have several fungicidal products that you can use to cure this disease. First, prune off and dispose of infected areas (don't let it drop into the soil to mix back in!). Avoid overhead watering. In the fall, rake up and destroy the fallen leaves. After pruning the plant in the dormant season, spray with a Lime-Sulfer product according to manufacture's instructions. Then when the new growth starts, begin a spraying program again. And, look to plant disease resistant varieties if this is a chronic problem.
Powdery Mildew: The most widespread and serious disease for roses, it also affects other plants such as, annuals, perennials and bulbs. Young leaves, young twigs, and flower buds are covered with a thin layer of grayish white powdery material. Infected leaves may be distorted and curled and many may turn yellow or purplish and drop off. New growth is often stunted, and young growth may be killed. Badly infected flower buds don't open properly. In late summer, tiny black dots scatter over the powdery covering like ground black pepper.
Powdery mildew is caused by a fungus, consisting of fungal strands and spores. The spores are blown airborne and infect other healthy plants. The fungus saps plant nutrients, causing distortion, discoloration, and often death of the leaves, canes and branches. Powdery mildew can affect a plant at any time during the growing season. In the fall, the fungus forms black spores that lay dormant during the winter, then spread during spring, but it is the most severe during the late summer and under humid conditions.
Bring in a plant specimen to The Plant Farm to determine the best treatment for your particular plant. When practical, pick off and destroy infected leaves. If the plant is severely infected, replacing it may be your best bet. Make sure the area you are planting in is free of disease infected debris. Pick disease resistant varieties.
Rust: Yellow to brown spots appear on the upper surfaces of leaves, usually in the late spring or early fall. The lower leaves are affected first. The underside of the leaves contain spots or blotches in red, orange, or black powdery material that can be scraped off. Infected leaves may become twisted and dry and drop off or remain attached. The plant lacks vigor.
Rust is caused by several species of fungi. Wind spreads the spores to healthy plants where they enter the underside of the leaves. Spots develop directly above, on the upper surfaces. These spores can survive winter on dead leaves and spread to new victims in the spring.
At the first sight of rust, pick off and destroy the infected leaves. Rake up and destroy any infected debris on the ground. Come into the nursery and ask us for the best fungicide for your particular plant variety. And, as always, try to plant disease resistant varieties.
Rose Aphids: These tiny green or pink insects cluster on leaves, stems and developing buds. When aphids are numerous, flower buds are usually deformed and may fail to open properly. A shiny, sticky substance often coats the leaves. Ants may be present.
Rose aphids (Macrosiphum rosae) do little damage in small numbers. Plants can tolerate fairly high populations without much effect. When aphids become too numerous to count, then damage can occur when the little beasts suck the roses dry of juices from the buds and stems, affecting flower quality. Also, the aphids gorge themselves so much, that they are unable to fully digest all the sugar in the plant sap and so excrete the excess in a fluid called 'honeydew', which drops on the leave below. This honeydew attracts a new problem, namely a sooty mold that causes the plant to look black and dirty. Also, ants like to eat the honeydew, so if you see ants around your roses, that may be a good time to look closer.
We carry several chemical solutions to aphid infestations, including an insect killer, insecticidal soap and lady bugs. The chemical solutions may need to be applied several times, according to manufacturer's recommendations. As soon as the food trough's empty, the ladybugs move on, perhaps to another infestation somewhere else in your garden.
Although the list of possible diseases are too large to fully cover here, we offer solutions at The Plant Farm to fit your needs. In addition to the chemical products we carry, we also offer beneficial insects. With concern for the environment, the use of beneficial insects is a natural way to control pests. Several bugs that we carry include:
Praying Mantis: A great bug in your garden before the pests arrive. They eat virtually any pest that moves in.
Ladybugs: Add color to gardens while fighting aphids, mealy bugs, leaf hoppers and other pests.
Beneficial Nematodes: Kill soil-dwelling and boring insects such as weevils, grubs, beetles, maggots and cutworms. Great for the lawn, they remain effective for several years.