Best spray for powdery mildew on squash

blevinandwomba Posts: 813 ✭✭✭✭
edited November 2020 in Pest & Weed Problems/Solutions

So we are planting extra squash this year, and Dash's video got me thinking about how I'm actually going to keep this crop alive. We live in a fairly humid valley, and get plenty of not-so-friendly fungi. Every year the Powdery mildew somehow manages to catch me by surprise; this year I am going to have a plan in place.

I have finally set aside a calendar just for the garden. Notebooks don't work well for me. This way, I can make a regular schedule of feeding and spraying as needed.

I was looking up spray recipes- I have done the baking soda version in the past- and I kept coming across the milk spray.

I was wondering, who has used either of these sprays, what is your experience, and do you think one is better? The baking soda has its ingredients in its favor- I always have baking soda, oil, and dish soap. No one in my house drinks milk, so I would have to buy it each time (Unless I could just snitch some of my Mom's half-and-half for her coffee- hmm, but I don't know if the fat content would be too high?) However, the milk spray is supposed to feed the plant as well as ward off mildew.

Please share your knowledge( or theories. I take those too.)


  • LaurieLovesLearning
    LaurieLovesLearning Posts: 7,210 admin

    I have heard of the milk spray working well. I have never had to use it though.

  • Torey
    Torey Posts: 5,396 admin

    A friend is having issues with tomato plants he started inside. I have sent him these links to see what he thinks. I will update any results he has.

  • Merin Porter
    Merin Porter Posts: 1,026 admin
    edited May 2020

    Has anyone had an issue with what appears to be powdery mildew on rosemary? We are in Zone 6a and so are currently growing it indoors under a grow light. These are plants we bought a couple of months ago.

    We put a fan on them as soon as we saw what was happening, but it doesn't appear to have helped. From what I'm seeing online, you're supposed to trim the affected leaves and apply that milk solution. But at this point that would basically mean throwing away the entire plant, because everything appears to be affected. I saw that we could use Neem oil on more severe cases, which may be what we need to do.

    Just curious about whether anyone else has dealt with this and how....


  • blevinandwomba
    blevinandwomba Posts: 813 ✭✭✭✭

    @Merin Porter could you try taking it outside during the day? Most of the time when my indoor plants get some sort of fungi issue, fresh air seems to help.

  • greyfurball
    greyfurball Posts: 591 ✭✭✭✭

    I use this method every year (the milk, vege oil and water).

    Now I also live in a hot and humid climate for about 2-3 months every summer so I will not say this works perfect but it has cleaned up about 80-90% of my problem each summer.

    Just three things to remember though, never spray on a day where rain is expected. If it happens, spray again the next day. Never spray close to the evening since you do not want your plants to be damp going into nightime. This just makes the fungal spores more prolific. Always make sure the plant and leaves therefore have time to dry out. And once your spraying schedule starts, don't get lazy and figure I will just skip this week (I always sprayed once a week). If you do you will learn to regret it.

    Also, as for the milk, we don't use milk either in my house so I got a hold of some dry powdered milk and use it. Ratio to mix is a 9 parts water to 1 part milk powder. Then add the 1 tablespoon of vege oil if you like.

  • greyfurball
    greyfurball Posts: 591 ✭✭✭✭

    I also forgot to mention it but always start your spray schedule BEFORE you start having the problem. If you prevent the spores from starting it is so much easier to control a small patch which might come on in summer. If your garden is already covered with it, it is much harder to control. Once the garden is overrun even the milk bath will not clean it up so you can start again with beautiful plants. If you remove all the spore-ridden leaves and burn them new growth will come out clean but it doesn't take long for them to get covered with mildew also.

  • greyfurball
    greyfurball Posts: 591 ✭✭✭✭

    And finally, over winter I always research my problems and see if I can find anything new. Some of these I already do each year anyway but a few of them I have not tried before so if you wish to give any a try this might help you also.

    Fungus In The Garden

    Depending upon your climate, fungal diseases in the garden is one of the hardest things to control IF you let it get started. Therefore, the trick is often to head it off in advance by using some common preventative measures. Check out these ideas to help you and your garden to navigate through the hot and humid, wet seasons of the year.

    ·        Combine these: ½ cup molasses, ½ cup powdered milk and 1 teaspoon baking soda. Mix these into a paste and place this paste into the toe of a nylon stocking. Tie the stocking off so it is about 12-18” long. Cut above your tie. Now place the stocking in one gallon of warm rainwater and let it steep for 3-4 hours. After steeping, strain the solids out (if needed) and mist all of your plants every two weeks as a preventative measure.

    ·        Sometimes, no matter how hard you try, blight, especially in your tomato patch, will set in anyway. If it does, and you are not able to follow the rules of consistent crop rotation, it is time to sterilize your soil. Use this recipe every Fall after your plants are removed and then every Spring before your tomatoes are planted. Combine 2 tablespoons of household bleach with 2 tablespoons of baby shampoo in one gallon of warm rainwater. Mix well, place in a handheld sprayer and spray the soil, lightly mixing this into the top level of the soil. Now plant your transplants. As a follow-up during the growing season, every 2 weeks combine 1 cup of compost, ½ cup Epsom salts and ½ cup of powdered milk. Combine these together and sprinkle some around the base of each tomato plant.

    ·        Some general rules for fighting fungal disease in the garden, at the time of planting is give each plant plenty of room so as the plants grow there is air circulation around every plant. The closer the plants are the greater the risk of fungal disease.

    ·        Also, as you trim or prune plants during the growing season, any plant which shows signs of fungal stress, prune off the leaves or limbs which show signs of stress and burn these. Never put these in the compost pile. After you have finished with one plant, before you go to the next plant, sterilize your clippers, pruners and your hands. Everything must be cleaned. It is recommended you do not wear gloves when you work in your tomato bed because the gloves must be sterilized also before moving on to the next plant.

    ·        During wet and humid weather you can also spray each plant with 3 tablespoons of apple cider vinegar mixed into one gallon warm rain water. Spray this one time weekly as another preventative measure.

    ·        Still having problems? Here is another possible solution, especially good for signs of powdery mildew on any type of plant. Mix 1 teaspoon of white vinegar, 1 teaspoon Listerine antiseptic mouthwash and 3 drops of liquid dish soap into a handheld spray bottle filled with water. Shake well and spray affected plants weekly.

    ·        Are you a smoker? Always wash your hands with soap and water before working in the tomato/potato plant bed. The tobacco mosaic virus (another type of fungal disease) can afflict both these types of products in your garden just from the residue on your hands from smoking tobacco.

  • Merin Porter
    Merin Porter Posts: 1,026 admin

    We could! I was hoping that putting the fan on it would help, but I think it's warm enough here to allow a few hours outside during the day.... Thanks! :)

  • kbmbillups1
    kbmbillups1 Posts: 1,272 ✭✭✭✭✭

    This is great! @greyfurball I wrote down all of your recipes. No matter what I have blight every year on my tomatoes here in Georgia. I have tomato plants that I grew from seeds that I'm waiting a few more days to plant. I tried alternating baking soda and peroxide last year as well as planting my tomatoes next to a trench filled with veggie scraps covered with dirt. They were the best tomatoes I've grown but in the end the blight won.

    Planting in a new spot this year. Hoping that helps as well.

  • Karin
    Karin Posts: 272 ✭✭✭

    We usually end up with blight/mildew on our tomatoes too, but I have found less of a problem if I remember to water first thing in the morning, and NEVER in the late afternoon or evening - that's a sure-fire recipe for mildew!

  • blevinandwomba
    blevinandwomba Posts: 813 ✭✭✭✭

    Thanks @greyfurball, that is a lot of good information! The molasses-milk-baking soda spray sounds like it would be the best of both worlds.

  • Momma Mo
    Momma Mo Posts: 138 ✭✭✭

    We just watched a video about using hydrogen peroxide solution followed by baking soda solution. It was done by The Rusty Gardner on YouTube.

  • dianne.misspooz
    dianne.misspooz Posts: 105 ✭✭✭

    Thank you to those that provide solutions to these pesky garden issues. I'm learning tons!