Intense Mildew Smell in soil

by Jay Perrin
(los angeles)

Thank you so much for responding to my question. My wife and I have a flower bed just outside our bedroom door that during any watering the soil reeks of an intense mildew smell. I am extremely allegic to mildew and the spores are getting into the bedroom and closing my airway. Is there anything that can be done to treat the soil and kill the mildew? There is nothing visible on the surface of the soil but it is clearly evident that the smell is coming from this area.

Hi Jay, so sorry to hear of your distress - how disturbing.

There are a couple of things that could help in this instance, but not knowing more about what kind of soil this is - some kind of garden soil?? Container soil?? and its make up - peat based?? it's hard to narrow down your options, so I'll just throw out a couple of ideas that might help:

First of all, I would alter the pH of the soil, by sprinkling on dolomite lime. Scratch it into the soil well. Most fungi prefer an acid based soil (think, pine needles; wood products like bark mulch) so altering the pH may abate the growth of the mildew.

Second, I would mulch quite thickly with a pebble mulch, or my favorite, lava rock. This will prevent the spores from splashing up when the area is watered, which might alleviate the whole issue.

Your third option, which may or may not be feasible, is to remove the soil and the garden bed, place pavers there instead and use containers to display your plants in.

It's important to keep the area dry if that's possible, because mildew and most other fungi rely on moisture to propagate.

Hope this helps with your issue.

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