A downside to wet weather like we have been having recently in Sydney is that your plants can become infected with powdery mildew. Powdery mildew is a fungal infection that is predominantly seen on the leaves of plants. It is very similar to black spot, which affects roses. I have had some of the curcubitsin my garden succumb to the disease over the past couple of weeks.
Now that the weather has been dry for a couple of days I decided to go out this morning and treat my poor curcubits. It seems to be mainly affecting my zucchini and squash plants which I have beside my driveway. They are partly shaded by trees in my neighbour’s yard, and it is likely that they do not get as much sun as some other zucchinis and the pumpkins that I have growing in a sunnier position at the other end of the same garden.
There are plenty of options available for treatment. you can use either anti fungal chemical sprays, or a commercially available organic alternative. Or you can use the no-frills option as I have, and use bicarbonate of soda.
That’s right, humble old bicarb soda, which is cheap as chips and sitting in your kitchen cupboard.
The theory is that powdery mildew does not like alkalinity. Bicarb soda is an alkaline substance, and so should make the conditions unfavorable to powdery mildew. I made up a solution of about 2 teaspoons to 500mL of water, put it in a spray bottle and sprayed it on the affected leaves. I have done this before, and it does work. And to boot the commercial organic product was mainly potassium bicarbonate and cost about $20. Bicarb soda is sodium bicarbonate and is cheap as! Seeing as it is the bicarbonate bit that I want to increase the alkalinity, you can see why I just went for bicarb soda.
Lets hope they look a bit more like my healthy plants soon.
Oh, and in an update to my potatoes, I got just over 5kg of Ruby-Lou, bringing the total to just short of 9kg potatoes from 22 tubers planted.