In honor of Garden Bloggers Death Day that will be celebrated at the end of the month over at Gardening Without Skills, I will show you what I've been doing in the garden to keep Death away. I haven't been totally successful, but I do what I can.
The weather here in the Boston area - really the whole North East - has been wet and cloudy. My trusty weatherman told me today that for the month of May and June we had only 7% of the days that were at least mostly sunny. If you do the calculation that means we had only four days that were mostly sunny in two months. The humid sunfree weather is fertile breeding grounds for fungal diseases. I have them in abundance around the garden.
What do I do to keep them at bay? First I pick off diseased leaves. Tomatoes are probably the worst offenders. Many stake their tomatoes and rigerously prune them to keep the air flowing. I don't. I cage mine (mostly - my potted tomatoes have stakes). So when the foliage gets really thick inside the cage, I prune the middle leaves out. They aren't getting much sun anyway. I also pick off all the leaves that show signs of any disease. I'm doing this with my potatoes too that have developed a case of late blight.
Second I spray. I started spraying last year after reading a recommendation from Love Apple Farm. I alternate two types of spray and spray every week. Last week I used a mixture of aspirin and worm casting tea. I take 1/2c of worm castings and soak it in water for a day. I strain the mixture into my gallon sprayer. Then I add 3/4 of an aspirin tablet dissolved in water and fill the sprayer to the top. I coat the tops and bottoms of all the leaves. I do this for anything that tends to get fungal diseases in the garden including tomatoes, potatoes, peas, beans, cucurbits and my rose.
Most people know the benefits of worm tea. It is a foliar feed and it has microorganisms that fight off diseases in the garden. Fewer have heard of using aspirin to help their garden. Aspirin works because it turns on the plants own disease fighting mechanisms. Whether I have to spray it every other week is questionable. Once that mechanism is switched on it may stay on for a long time. The research for this has been done on tomatoes. Even if it doesn't help any other plant that one would make it worth my while. Tomatoes are the most disease prone plants in the garden.
This week I sprayed Serenade, which is a commercial biological fungicide. It contains a bacteria called Bacillus subtilis that kills fungal spores.
There are so many other solutions that people use for fungal diseases - skim milk (1:9 with water), baking soda (1-2T baking soda, t vegetable oil, 1 gallon water). But so far I've been fairly happy with my two remedies. They aren't perfect by any means. Nothing will stop powdery mildew around here at the end of the season, but it does keep Death at bay for a while longer.