“My red rhododendron looks as if it has a layer of ash or white powder on it (above). What should I do?” asks Birds & Blooms reader Steven Graves of Aptos, California. Horticultural expert Melinda ...

Powdery mildew is a fungal disease affecting many plants, causing a white or gray coating on leaves and slowing growth. The fungus thrives in warm, dry weather with high humidity, especially in ...

Roman Gonzalez is the creator of the urban gardening blog MrBrownThumb, founder of the Chicago Seed Library, and a co-founder of One Seed Chicago. Powdery mildew is a widespread and easy to recognize ...

When powdery mildew pops up on your roses, here's get rid of this common plant disease fast. Powdery mildew appears as white or gray spots on roses, usually during warm, humid conditions. Catching ...

I had some beautiful columbines in pots that were killed by powdery mildew. I saved the seeds. Now I have 12 plants with signs of mildew. Should I let them go dormant, or fight the mildew with a ...

Q. Is there any way you could help in figuring out what is wrong with our lilac? – C.B. via email. A. Lilacs are quite susceptible to a fungal disease called powdery mildew, which causes a ...

Q: Last year my grapes had such bad powdery mildew that even the grapes dried up and looked moldy and shriveled. I was told by the master gardeners at the farmer’s market that I needed to do something ...

Powdery mildew – or PM – can be a farmer’s worst nightmare. The mildew is easy to spot as it appears on the leaf as a matte-white frost—almost like that fake snow spray you often see around Christmas ...

The grayish white powdery growth you are seeing on the dahlia leaves is caused by a fungus and can also be a common garden problem on other plants. Many species of fungi can cause powdery mildew on ...

The worldwide distribution of one of the most important cereal pathogens is the result of human activity. Researchers have traced the history and spread of wheat powdery mildew along wheat trade ...

One of the best parts about having a garden in the summer is watching your plants grow throughout the season. But if you’re out gazing at your garden one day and notice some white circular spots on ...