What is the white stuff on my boxwoods?

Apply a spray of 1/4 teaspoon baking soda mixed with 1 quart of water. Spraying plants weekly at the first signs of fungus on leaves can protect plants against further damage. Use neem oil, a commercially available organic treatment.

Boxwood mite Infested leaves appear to be pin-pricked or stippled with tiny white or yellow marks. The boxwood mite is a pest of both European and American boxwood varieties. Japanese boxwood is less susceptible.

Using a fast stream of water from the hose, wash mites from the boxwood foliage. If this approach isn’t working, you can spray the foliage in summer with horticultural oil. As a last resort, treat the boxwood spider mites with abamectin (Avid), bifenthrin (Talstar), malathion, or oxythioquinox (Morestan) in early May.

Boxwood blight – Blight turns leaves spotty and brown, and may cause them to drop. It also forms cankers on the wood and, in wet conditions, white fungus all over. Cut away and dispose of affected branches and leaves. Put down new mulch to prevent spores from splashing up from the soil, and apply fungicide.

The Basics of Powdery Mildew And unlike most types of fungi, they cause more severe cases of disease in warm, dry weather. A mild case may go away on its own. But without intervention on the part of the gardener and a little extra TLC, a severe infection can mean the end of your precious plants.

Combine one tablespoon baking soda and one-half teaspoon of liquid, non-detergent soap with one gallon of water, and spray the mixture liberally on the plants. Mouthwash. The mouthwash you may use on a daily basis for killing the germs in your mouth can also be effective at killing powdery mildew spores.

The disease causes black spots to form on leaves, along with elongated black lesions on twigs and stems. Rapid defoliation (in a matter of weeks) soon follows the initial symptoms of infection. Circular leaf spots and twig lesions are early indicators of boxwood blight infection.

The Boxwood Leafminer is the most damaging insect pest to boxwood in the Mid-Atlantic area of the United States. Technically not a leafminer, but a midge, this pest causes blisters and defoliation that can be quite an eyesore for a boxwood enthusiast.

What Exactly Is Insecticidal Soap? The active ingredients in insecticidal soap are potassium salts of fatty acids (also known as soap salts), which are created when the chemical compound alkali mixes with the fatty acids found in natural oils, including castor oil, coconut oil, and olive oil.

If you choose to use a pesticide, apply when the new leaves are fully formed, around May 1st when the Weigela is in bloom. Make a second application between mid-June and mid-July. Use carbaryl (Sevin) or malathion to control adult flies. Acephate (Orthene) applied in mid-May (about 3-4 weeks after the adults emerge.)

Powdery mildew is a common fungus that affects a wide variety of plants. It is easily identified and appears as light grey or white powdery spots usually found on infected leaves, but can also be found underneath, or on stems, flowers, fruit or vegetables.

The most detrimental pest of boxwoods is the boxwood leafminer. It is a small fly that is indigenous to Europe but is now found throughout the United States. Both adults and their larvae cause serious damage to the boxwood foliage in the form of blistering and discoloration.

The main difference between powdery and downy mildew is that powdery mildew looks like spilt powder on leaves, whereas downy mildew causes leaves to droop and develop yellow and brown spots. … Generally, powdery mildew is an ascomycetes fungi, while downy mildew is an oomycetes fungi.

1. Mix 1 tablespoon baking soda with 1 tablespoon vegetable oil and 1 teaspoon dish soap in 1 gallon of water.
2. Mix 4 tablespoons baking soda with 2 tablespoons of Murphy’s oil soap in 1 gallon of water.
3. Mix 2 to 3 tablespoons vinegar with 1 gallon of water. …
4. Neem is an organic fungicide.

Unlike some other diseases, powdery mildew spores do not live in the soil, but rather are transferred from plant to plant by the wind, notes Rutgers New Jersey Agricultural Experiment Station. … If possible, plant cultivars that are resistant to powdery mildew and be sure to rotate crops in your vegetable garden.

Powdery mildew, mainly caused by the fungus Podosphaera xanthii, infects all cucurbits, including muskmelons, squash, cucumbers, gourds, watermelons and pumpkins. In severe cases, powdery mildew can cause premature death of leaves, and reduce yield and fruit quality.

Plants infected with powdery mildew look as if they have been dusted with flour. Powdery mildew usually starts off as circular, powdery white spots, which can appear on leaves, stems, and sometimes fruit. Powdery mildew usually covers the upper part of the leaves, but may grow on the undersides as well.

Cornell University discovered a weekly application of one Tablespoon baking soda mixed with 1 teaspoon insecticidal soap or light weight horticulture oil (these act as spreader stickers) in a gallon of water will suppress powdery mildew. The organic fungicide Neem and other commercial products can also be used.

The blight begins with dark or light brown spots or lesions on the leaves. The leaves turn brown, fall off while the stems develop brown or black lesions. The leaves are lost very quickly after the first signs of the disease appear. The roots are not attacked and the plant may try to put out fresh leaves.

• Leaves turn brown and fall, leading to bare patches.
• Black streaks and dieback on young stems.
• In wet conditions the white spore masses of the fungus may be seen on the undersurfaces of infected leaves (place leaves in a plastic bag with moist tissue for a few days to check).

You may be able to keep boxwood blight at bay on remaining unaffected foliage by spraying a chlorothalonil-containing fungicide every 7 to 14 days during the growing season when temperatures are above 60 degrees F. Reapply if it rains — the fungus thrives in warm, humid weather.

Professionals control boxwood leafminer by applying a systemic insecticide in spring (usually in March to early April). This kills the larvae inside the leaves before they can emerge as adults to lay new eggs. It’s generally more effective than targeting the adults later in the season.

The most common method to rid plants of leaf miners is to spray general pesticide on the infected plants. The trick to this method of how to kill leaf miners is to spray at right time. If you spray too early or too late, the pesticide will not reach the leaf miner larva and will not kill the leaf miner flies.

Boxwood leafminer larvae voraciously feed as they mature in spring, leaving a fragile, translucent “window” of leaf tissue on the lower leaf surface. As they pupate, they work their way through this thin leaf tissue to facilitate the emergence of adults—which is the cause of the crackling sound.

Spray once a week (or for more serious infestations, every 4 days) for 4 weeks until you see improvement. Any more or longer than that, and you risk leaf injury, as the soap will remove all the natural oils and waxes that protect the leaf, and thus remove the plant’s natural defenses against pests and diseases.

Dawn dish soap is safe for plants if you use a small amount diluted with water. It does contain chemicals that can be abrasive and harm plants if used in large amounts. … If you use too much, it can be toxic to the plant and disintegrate the leaf’s waxy coating known as the cuticle.

A simple solution made from liquid dish soap and water will kill adult whiteflies without harming plants. Add 1 tablespoon of liquid dish soap to 1 gallon of water and mix well. Pour the solution into a plastic spray bottle and spray it on all infested plants, saturating the leaves’ upper and undersides and the stems.

Insecticide sprays containing bifenthrin (Ortho Bug-B-Gon), carbaryl (Sevin), cyfluthrin (Bayer Advanced Yard and Garden Spray) or malathion are among the recommend materials that can be applied to control the adult flies.

Perfectly timed, just as the healthy new flush of spring growth leafs out on your boxwood shrubs, small orange flies may be visible fluttering around your boxwoods. This is the mating season for adult Boxwood Leafminers.

amyamyamyamyamyppppp. FYI, I just sprayed my boxwood which was “alive” with the gnats, who were laying eggs. I sprayed the shrub with Neem oil, and the gnats are now dead and dying on the ground, so it is quite effective during an active infestation. … All of my other boxwoods are healthy and not infested.

A white mold growing over the surface of houseplant potting soil is usually a harmless saprophytic fungus. … Overwatering the plant, poor drainage, and old or contaminated potting soil encourage saprophytic fungus, which feeds on the decaying organic matter in soggy soil.

The fungi that cause powdery mildew thrive in warmer, humid conditions, but can also be found in drier climates. They can even spread to greenhouses or indoor plants, as the tiny spores that spread the disease can pass through window screens or other tiny openings.

Acephate is a foliar systemic insecticide, and sprays will control boxwood psyllids. Soil treatments with dinotefuran or imidacloprid will control psyllids, but may take two weeks or more to begin providing season-long control.

The life cycle of powdery mildew includes both sexual and asexual reproduction. Asexual spores produce conidia and the sexual stage produces cleistothecia (ascocarps or fruiting bodies) which contain ascospores.

What does downy mildew look like? Downy mildew symptoms begin as small, green or yellow, translucent spots that can eventually spread to an entire leaf, stem, flower or fruit. Infected plant parts may eventually brown or bronze.

While both diseases are common on a wide range of plants, diseases caused by the downy mildew pathogens are generally more destructive and more difficult to manage.