Friday, June 24, 2011

Got Milk? Another look at garden fungus

Last week we shared that we are starting to have some trouble with fungal disease on some of our plants. The tomatoes, especially our yellow pear cherry, our mystery squash, our sunflowers, and some of our cucumbers are showing the most signs of this problem. Our roses also broke out with rust, a type of fungus that can quickly get out of control.

Rust fungus on bottom of rose leaf
In addition to rust, we also have early tomato blight and powdery mildew cropping up throughout the garden.

Early tomato blight above and powdery mildew below


Last week when I told you about our fungal issues, I told you I was going to use copper spray to try and get them under control, but I have decided to change my approach. I am lucky enough to get advice from some more experienced gardeners than I am, and I am going to take that advice. 

Copper is an organic solution but like many organic sprays, it can have a negative impact on beneficial insects and I don't want to be responsible for injuring any good bugs. 

California Carpenter bees are good.
Copper can also build up in the soil over time and while in very small amounts, copper is essential for our health, too much of it can have a negative effect. I am keeping the copper in my arsenal to use occasionally if I feel like it's absolutely necessary but I am going to try milk instead to try and get a handle on the situation. 

I am not a fan of milk, or of the conventional milk industry, which was my initial hesitation in using it in our garden. I don't purchase conventional milk for my own consumption. Ever. Purchasing raw, organic milk would make me feel better about it, but that's not an affordable option. Milk is an effective solution, that is not harmful to insects, nor will it cause a build up of metal in the soil, so I'm buying milk for the garden. 

My more experienced friend says that powdered milk was as effective as fresh in a study, so that is what I am going to use. I have not had a chance to get powdered milk yet so last night I purchased a container of California, hormone free milk from the corner store, to get a start on trying to manage this fungus. 

My beautiful garden helper, Larisa, stealing Gidget's photo op.
We mixed a 9:1 solution of water and milk in the 1 gallon sprayer and applied it to all of the susceptible plants in the garden.

Larisa applying the milk solution 
We waited until the evening and sprayed the plants only after they were no longer in direct sun. With the 9:1 solution, we will be applying the milk every 3-4 days. Some people suggest a stronger solution and spraying less often.

Prevention is a better solution.
Doing everything you can to prevent these problems is the best way to go but even extremely careful gardeners experience issues with fungal diseases. Some of the things you can do to minimize these problems are:
  • Make sure your plants have plenty of air circulation
  • Mulch heavily under plants to help prevent spores from spreading from your soil to the lower leaves of the plants.
  • Don't water plants from above, especially during warm weather. 
  • Sanitize tools and wash hands after working with affected plants. I use 1 cup of bleach in a gallon of water and soak my tools in that for 10 minutes and then dry them well.
  • When trimming affected leaves, do not let them come in contact with non affected leaves. 
  • Burn or dispose of affected foliage. Do not compost it. 
  • Keep fallen leaves cleaned out from under your plants.
Sometimes it may be a good idea just to remove an entire plant or prune it all the way back if you have one that is badly affected. I chose to do that with a couple of my roses because of their proximity to the vegetable plants.

Mr Lincoln rose pruned all the way back
After cleaning all of the dead leaves out from under the plant, I worked some corn meal into the soil which can also help prevent the spread of fungus.

Gidget is not happy. She thought the milk was for her and she's concerned that  Larisa is trying to steal her garden. 

1 comment: