Whether in Africa or Canada, indoor farmers have to deal with similar pests. One that's constantly battering our crops is powdery mildew, which is especially ruthless to our mustard crops, and consistently infests our greens. If you are running a commercial farm, a powdery mildew infection can significantly impact your sales and rob you of a large portion of your revenue.

Let's cover some general tips to keep diseases away, then hone in on the control of powdery mildew.

The best way to avoid crop loss from disease is to be hyper-vigilant about avoiding the entry of those diseases in the first place.

This means keeping things clean to disallow spores from entering your growing space, monitoring what goes into your compost pile, and knowing how to sterilize your system safely.

For instance, some precautions we take in our aquaponic greenhouse are keeping a separate discard bucket for powdery mildew-infected plants and keeping a separate discard pile of those plants that is far away from our good compost pile.

You can also use resistant varieties and crop rotation, which disturbs the life cycle

(Quick tip: Sulfur and copper are two active ingredients that will work well to control a variety of diseases. Sulfur burners are available from many sources, and copper sprays are available as a fungicide. In aquaponic systems, always ensure that fungicide sprays will not harm your fish.)

A common and destructive enemy

Powdery mildew. If you grow greens, peppers, or tomatoes, there’s a good chance that you've encountered this unpalatable pest.

Partial to hot and humid climate (such as the inside of your greenhouse), powdery mildew appears first as lightened yellow patches on leaves, and/or a coating of white powder, and often stunts plant growth, shortens crop lifespan, and makes infected growth unsaleable.

If you spot powdery mildew in your greenhouse, remove infected material immediately and with as little disturbance as possible.

Discard the infected plant matter, but do not compost it! 

Powdery mildew spores are hardy and will stay viable through a composting process.

If you are growing with hydroponics, you can use serenade spray to manage powdery mildew.

Do not use Serenade with aquaponics.