Gardening and Landscaping Stack Exchange
Gardening and Landscaping Stack Exchange

Questions tagged [mildew]

15 questions
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Are these Holly tree leaves affected by White Mildew?

I just noticed that one of my Holly trees has some leaves with white tips like these: It doesn't quite match pictures I've seen of White Mildew online, but I've never noticed this before so wanted to determine if this was anything serious. My…
Derek
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Powdery mildew on oak (Erysiphe alphitoides?)

I have an oak (Quercus robur) sapling I've grown from seed in a pot (it is 2 years old) and its leaves are exhibiting a powdery white mildew. After some searching online I think it's a case of erysiphe alphitoides (it looks exactly like the…
Matt Hogan-Jones
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Diagnosing white fuzz on kale. Is this powdery mildew?

I think I'm dealing with powdery mildew, but I want to confirm that diagnosis. Context: I'm in Portland, OR. I've got several raised beds with a couple kinds of kale, broccoli, brussels sprouts, some beans, cucumbers, and few other things. The soil…
emersonthis
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How effective is neem oil as a preventative measure against powdery mildew?

I regularly use neem oil in my garden to help suppress the presence of white flies, aphids and certain soft-body caterpillars. I'm curious if neem oil can be effective in addressing powdery mildew on cucumbers or pumpkins. I'm in NY zone 7a and grow…
JRap88
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is this powdery mildew growing on my young carrots?

I can't tell if this is powdery mildew as it doesn't seem powdery and is instead concentrated blobs of white. It also doesn't come off when I wipe it, unlike the videos I've seen. The leaves are still young and haven't had time to fully develop…
Craig Ratcliffe
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Does it make any sense to heat soil in an oven in effort to kill pathogens?

So this year, a lot of my inside potted plants got attacked by powdery mildew and other afflictions. All affected were previously given soil that I sifted from the composter that is on the porch of our building. Likely, some people in the building…
Tomáš Zato
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Is having moss in your terrarium similiar to a layer of activated charcoal?

I am making a terrarium and almost everywhere (on the web) it says to add a layer of activated charcoal between the soil and drainage rocks. I plan on creating a sort of 'meadows' look by making small hills and planting it with moss then adding a…
user16651
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Should I be Concerned About Mildew, etc. on Mulch?

Sadly, the brand names for bagged mulch found in the "Big Home Improvement" stores are pretty low quality nowadays. I put down some recently in my garden bed and almost immediately after a big rain noticed what I assume is some sort of white powder…
AA040371
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What are these white spots on the leaves of my fig tree?

I have a fig tree in my flat and some white spots have appeared and get more and more numerous and spread more and more over the leaves. It is not removable when rubbing with a tissue. I can't find what it is, it does not seem to be common on fig…
Noil
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Why does this zz plant have white residue and holes?

My ZZ plant has developed a thin white residue and holes on some of the leaves. We have had the ZZ plant about a month where it sits in a corner of the bedroom by a window. We have watered it once in that time. What might be the problem? And how do…
Peter Hickman
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How do I tell the difference between fungus and natural coloration in zucchini?

I've read that white patches on zucchini can be natural, powdery mildew, or another fungus. How do I know which? 2 of my zuchinni have large patterns of white areas on all leaves older than about a week. New growth seems to be coming in without…
Matt Flamm
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What kind of orange tree disease (or not) is this?

There's a white discoloration on the leaves of my satsuma orange tree: Photos: https://i.stack.imgur.com/2aYcy.jpg I'm uncertain if this is something that needs to be treated, or if it's just residue from a spray at the nursery. It came like this…
Citizen
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Is There Powdery Mildew On My Lily Plants?

Recently, there was a large rainstorm in my area, which soaked my lilies’ leaves thoroughly. Afterwards, and even for a while before then, I had noticed small white dots on their leaves. If this is powdery mildew, what should I do about it? I’m…
Anonymous Pineapple
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Is this powdery mildew? Plant is potted and was unwatered for a long period

A potted everlasting sweet pea in my garden nearly died due to lack of water earlier this year. I managed to revive it but its older leaves are yellowing and have what looks like powdery mildew coating many of them. The upper leaves are largely…
Rob Bell
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Treating powdery mildew

Our tomato plants got powdery mildew problem, because of wildfire at west coast, there was not much sunlight, and even some leaves at top has powdery mildew problem, as you can see in the first picture. I have already cut some leaves and branches at…
user8142520
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