Katie Laffey from Healdsburg asks: I've seen dried sunflowers in an arrangement and they looked beautiful. How do you dry sunflowers?
Here's an easy way to dry your sunflowers to add to a dried-flower arrangement. When the flower heads sag down, cut them off, leaving enough of the stem so you can hang them upside down. Keep them in a well-ventilated room for about a month or two, out of direct sunlight. The process works better for the smaller varieties than the larger ones.
Kelly L. of Windsor asks: What is this white stuff covering the leaves of my roses? It looks like someone dusted them with baby powder.
Powdery mildew is a fungus that makes its yearly appearance on many varieties of roses and other perennials and shrubs. It is very prevalent under the dry summer conditions we have. It attacks all new growth including buds, shoots and flowers, including the leaves. This disease can be serious on plants such as dahlias, roses, crape myrtles, penstemons and sycamores, just to name a few.
If your plants have been hit by this white, powdery-looking substance, or if you want to stay ahead of the curve and keep powdery mildew at bay, consider the following helpful hints: Avoid excess fertilizer. A good alternative is to use slow-release fertilizer.
Overhead sprinkling may actually reduce the spread of powdery mildew because it washes spores off the plant; also, if spores land in water, they die. The best time to irrigate is in mid-morning so that the plants dry rapidly, reducing the likelihood of infections by other fungi.
Space plants properly for adequate air circulation. If you want to pick or prune off the infected leaves, that's fine. Try to select plant varieties that are resistant to powdery mildew. Of course, there are no guarantees — resistance does not mean immunity.
Rake up and dispose of all fallen leaves and garden debris. Certain fungicides, chemical or organic, can be used to manage powdery mildew when it's first detected on your plants.
In some situations, especially when growing roses, fungicides may be needed. The fungicides act as protectants, eradicants, or both. A protectant fungicide prevents new infections from occurring, whereas an eradicant can kill an existing infection. Apply protectant fungicides to highly susceptible plants before the disease appears. Once the mildew takes hold, it's difficult to control with a fungicide.
There are many less-toxic fungicides available, including horticultural oils, neem oil, sulfur, potassium bicarbonate and bicarbonate of soda (baking soda). A fungicide can be made at home by combining 2½ tablespoons of horticultural oil (Sunspray Ultra-Fine, Saf-T-Side, etc.) in a gallon of water and adding 4 teaspoons baking soda. This solution is sprayed on plants to prevent powdery mildew infections.
