Q.What Is Wrong With My Grape Vines?
I live in AZ it has been 105°. The leaves are changing color and getting spotty. How often should I be watering? I have noticed white fuzz on some parts of the stem. Are there several things going on here? Thank you for your time!
Certified GKH Gardening Expert
It is a fungal infection from overwatering.
Compensation for heat should be in the form of shade, instead of supplemental watering. Watering should, only, be done when the soil is completely dry down to about 3 or 4 inches. Overwatering, even in the heat, will lead to root suffocation and infection. Roots use the action of soil drying out for all processes including breathing and nutrient absorption, so soil that does not have a chance to dry out thoroughly will be the primary cause for infection.
Treatment will consist of fungicide and proper watering practice.
Here are some articles that will help you from here:
https://www.gardeningknowhow.com/garden-how-to/info/using-fungicides-in-garden.htm
https://www.gardeningknowhow.com/special/organic/biofungicide-information.htm
https://www.gardeningknowhow.com/garden-how-to/info/homemade-fungicide.htm
https://www.gardeningknowhow.com/edible/fruits/grapes/growing-grapevines.htm
