How to Water Squash Plants With Milk


Squash, zucchini, cucumber and other garden plants often come under attack by powdery mildew, which disfigures and weakens the plant. Powdery mildew can be identified by a dusty white or tan coating, and curling or twisting leaves. Spray a weak solution of milk and water on your squash and other plants to combat powdery mildew in a natural, organic matter. Cow's milk has germicidal properties, fertilizes the soil and provides nutrition to your squash and other plants.

Step 1

Create a solution of one part milk to three-to-nine parts water. Higher concentrations of milk will fight powdery mildew more effectively, but may also cause mold to form on your squash plants. Consider using skim milk, which contains no fat and won't go rancid and produce odors as it dries on the plant.

Step 2

Transfer your milk-and-water solution into a sprayer or misting bottle.

Step 3

Spay the leaves of your squash and any other plants infected with powdery mildew with the milk-and-water solution. Do not drench them; a light coating on the tops and bottoms of the leaves will suffice.

Step 4

Store any leftover milk-and-water solution in the refrigerator for up to one week, or use the solution to water your garden plants.

Step 5

Repeat applications of the milk-and-water solution once or twice a week for as long as necessary to fight powdery mildew on your squash plants.

Tips and Warnings

  • Only cow's milk will eliminate powdery mildew. Soy milk, rice milk and other non-dairy milks may provide trace nutrients, but they do not have the same germicidal qualities as cow's milk. No studies have been done on the effectiveness of milk from other animals, although some gardeners report anecdotal success with goat's milk.

Things You'll Need

  • Cow's milk
  • Sprayer


  • Biologischer Pflanzenschutz: Effectiveness of Cow's Milk Against Zucchini Squash Powdery Mildew
  • Ross Koning, Biology Department, Eastern CT State University: Plants and Milk
  • Simple Gifts Farm: Powdery Mildew
Keywords: powdery mildew, cow's milk squash, milk-and-water solution for plants

About this Author

Sonya Welter worked in the natural foods industry for more than seven years before becoming a full-time freelancer in 2010. She has been published in "Mother Earth News," "Legacy" magazine and in several local publications in Duluth, Minn., including "Zenith City News," for which she writes a regular outdoors column. She graduated cum laude in 2002 from Northland College, an environmental liberal arts college.