Califonia Bountiful

Gardening Q&A

Sept./Oct. 2014 California Bountiful magazine

As a California Bountiful reader, you have the opportunity to get your seasonal gardening questions answered by gardening expert Pat Rubin. Here are a few questions from other readers.

My roses, dahlias and zinnias all have powdery mildew. What do I do to keep this from happening next year?
It seems all sorts of plants get powdery mildew. The leaves look as though they have a coating of a powdery substance. The solution is to spray the plants with 2 1/2 tablespoons of horticulture oil (available at all nurseries) and 4 teaspoons baking soda in 1 gallon of water. Don't spray when temperatures are above 90 degrees. I used to get dry-air mildew on crape myrtles and was told to spray the leaves with water occasionally to wash it away. The plants never seemed to get it where the sprinklers hit, so that made sense.

What is a cover crop?
A cover crop is one you plant while your garden would otherwise be fallow. They are planted to improve the soil by allowing water penetration, reducing weeds and preventing erosion. Often, cover crops are turned under at the end of the season to add organic matter to the soil. Cover crops include clover, alfalfa, peas, beans, marigolds, mustard and rye, among others.

About Pat Rubin, California Bountiful's gardening expert

Pat Rubin

For Pat Rubin, gardening is more than just dirt and plants. "It's about history, romance, adventure and people," she says. "And it should be fun."

California Bountiful's gardening columnist has lived and chronicled this fun, hands-in-the-dirt approach for years—and for additional publications including Fine Gardening, Pacific Horticulture, Christian Science Monitor, Family Circle and The Sacramento Bee. Pat has also volunteered as a Master Gardener, speaks to garden clubs and appears regularly on gardening radio shows.

Need gardening advice? Ask the expert!

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