How to Stop Mold or Mildew on Grapes


Mildew and mold can ruin the beauty and productivity of grape vines

Grape vines are both decorative and useful additions to the garden. They provide a way to green up fences and walls that would otherwise look dreary. They can pour over archways or patio covers adding a Mediterranean design to the landscape. They also offer tasty fruits that are good for you and handy to eat since they come in bite-sized packages. For people who love their wines, there are many different wine grapes to feed the hobby of wine making.

There are also so many different varieties of grapes that most areas of the country can find a good selection to match almost any climate. But one thing that can take the fun out of growing grapes is discovering that your rich, green leaves or swelling fruit is covered with a white or gray powdery blush. This is mold or mildew, a fungus that grows on grapevines. It will not hurt you to eat grapes with mildew, but the fruit isn’t very pretty and the flavor can be affected. Severe attacks of mold can damage the health of vines.

Although you can spray your vines with fungicides, there are two better, organic ways to stop mildew or mold on grape plants.

The easiest way to avoid the problem is to plant American varieties. It is the European grapes that are most prone to developing mildew problems. Even in hot, dry areas, mold can still be a problem. If you can find varieties that will suit your taste, opt for naturally resistant plants like most of the American grapes.

The second way to stop fungus problems is something I learned while in England many years ago. Sulphur dust is a low cost treatment that is perfectly safe to use. It can be applied as a dry powder or mixed with water and sprayed. Do not apply it when temperatures rise over eighty five degrees Fahrenheit. And make sure you wear gloves, eye protection and even a mask. The dust is an irritant. My eyes burnt badly for a whole day when I decided to just add a little more to one missed spot and didn’t bother putting on glasses. Don’t do it!

Sulphur dust is best applied right after flowering as the tiny fruits begin to swell. Cover leaves and fruits lightly. Sulphur is said to be a good way to combat mites and other garden insect pests, too. It does stop mold and mildew on grapes. And it is organic.


Basic gardening terms and definitions: Organic Seeds

collect seed

Organic seed is harvested from organically grown plants.

Organic seeds are produced and harvested from organic plants – plants that are free from exposure to hormones, inorganic chemicals, fertilizers, insecticides or herbicides. There are strict requirements for foods and seeds that are certified organic which include careful, detailed records making sure organic materials are not exposed to sewage sludge, synthetic chemicals, and other prohibited substances. Not all countries have the same regulations for certifying seed as organic.

Most seeds for sale are controlled by companies that regularly produce genetically engineered material (GEO)  and may contain elements developed for improved profit-making growth rather than safe eating. These seeds might produce food that could prove dangerous to your health. There are many arguments and a lack of clear, definitive proof one way or the other at this point. Many seeds for sale are also coated with fungicides for better germination. You will be adding these chemicals to your soil if you use the seed. The safest way to avoid these issues is to buy your seed from companies that only sell organic, non-engineered material. If you are not growing edibles, you still can benefit your soil by avoiding treated seed.

Once you have grown your plants, you can let a number of your plants flower and collect the resulting seed for the next year’s use. Unless you can carefully control pollination, you may see variation in the plants you grow for the next generation. Cross pollination and reversion means that genes can combine differently in a natural process producing slightly different flowers and vegetables from the original plant where collection was done.

Organic plants and seeds are likely to cost more since they are produced without the efficiency of using mass-production chemical or genetic intervention. The choice usually ends up between saving money or taking the extra step of assuring your health, that of your family, and that of your soil (and the planet). In times of financial stress, the choice may not be so easy.