Treating An Outbreak of Powdery Mildew

Powdery Mildew

At this time of year, you may be seeing some mildews and other fungal problems creeping into your garden. There are a wide range of different mildews that can impact your crops and other plants, many specific to a particular species. Roses, and certain fruit trees and bushes can be prone to mildews, while there are other mildews that will affect cucurbits like cucumber courgettes and squash. Powdery mildew is a superficial fungal growth that covers the leaves, stems and sometimes flowers and fruit of a plant. It is easy to recognise the white, powdery patches on the leaves.


Crucifer Powdery MildewIn an organic garden, you can reduce the impact and halt the spread of powdery mildew, but there is no way to completely eradicate it. Once you have seen the problem, unfortunately you will likely have infectious spores around and you can likely anticipate a resurgence next year unless you are particularly careful.


You can reduce the number of spores by being scrupulous about removing any infected foliage immediately. Never put these on the compost heap as this would cause the spores to spread. Instead, simply remove these entirely from your garden.


Another measure that you could try is to treat surrounding foliage with a solution of milk and water. Scientists are not entirely sure why, but this treatment seems to reduce spread of the problem. As a preventative measure, spray leaves with a mix of 30% milk, 70% water. It is thought that it is the protein in the milk that helps, though this still needs to be studied in more depth. Unfortunately though, this is unlikely to save plants that are already badly affected. It can, however, be used perfectly safely on food crops.


Curcurbit Powdery MildewThe key thing with powdery mildew is to remove anything with white powdery patches immediately and stay vigilant. By removing infected foliage you can stop the problem from becoming a major issue.


If your garden is prone to powdery mildew, there are certain things that you can do to reduce your chances of having the problem in the first place. Mulching, and good watering practices can help a lot. Always make sure that you water the roots and not the leaves. Dry roots and wet leaves are a recipe for a powdery mildew problem, so try to do your best to avoid that scenario.


All organic gardens will have the occasional problem with pest and disease and that is totally normal. Just take preventative measures where possible, improve balance in the ecosystem and stay on top of problems and you will find that, generally, problems are not insurmountable.

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