Can I use a mixture of Borax and water on my zucchini plants; if so, what is the ratio of Borax to water?
Using Boron on Zucchini Plants.
Certified GKH Gardening Expert
Make sure that you know that this is an actual boron deficiency before you apply anything like this, as it is rare for there to be a deficiency like this. Adding more than is necessary will do much more harm then good for plants, as it is very easy to create a toxic environment with this.
If you can include photos, I can help you to determine the best course of action for the issue at hand.