Gardeners who heat their homes with wood derive a special benefit from wood ashes. Though ashes can make a mess on the hearth, they also have valuable nutrients for plants and -- even more important -- more acid-neutralizing capabilities pound for pound than ground limestone.
Wood ashes are high in potash, which invigorates plants and increases resistance to disease. Another ingredient, potassium, is important to root development and to new growth such as buds. Most hardwood ashes also contain about 1.5 percent phosphorus, according to "Organic Plant Protection."
Because wood ashes are so alkaline, be careful not to apply too much -- especially in a small area. Too "sweet" a soil can be as troublesome as soil with too much acid. If your soil is very acid, wood ashes won't hurt a bit. But if you're not sure, check your soil's acidity through a lab, your extension service or a do-it-yourself litmus test. You can get a litmus kit from your garden center. Moisten a soil sample with distilled water, then dip the litmus paper in it. When it changes color, check it against the chart in the litmus kit to determine its acidity.
In the perennial bed, keep wood ashes away from acid-loving azaleas, but sprinkle them freely on peonies and roses, which will bloom with greater color if fed ashes. (Spread them on the ground, of course, not the plant.)
If you have heavy clay soil under your lawn, wood ashes will help break it up. The extra phosphorus also will help your grass grow better. Use up to 15 pounds of ashes (a large bucketful) for every 100 square feet of lawn.
You can also add wood ashes to your compost pile instead of adding limestone. Or you can use them this summer for keeping down garden bugs. Scatter ashes around the plant base to drive off snails, slugs and other crawling creatures. Many other pests can be discouraged by sprays and dusts containing wood ashes.
If you're not going to use your wood ashes right away, store them in a place where they won't get wet. If left outside, most nutrients will leach out and into the ground over the winter. HOUSE-PLANT HINT -- Check house plants periodically for signs of mealybugs, spider mites and scale. Mealybugs are easy to spot because of their white powdery coat. Spider mites are microscopic, but you can usually see their fine cobwebby threads from leaf to leaf. Scale is relatively easy to spot and looks pretty much like its name (in brownish or cream colors). Mealybugs and spidermites generally can be controlled by spraying the plant with rubbing alcohol. Wait a few minutes, then rinse the foliage with tepid water. To prevent alcohol from getting into the soil, cover it with aluminum foil. Scale can be removed with pure soap (detergents may damage foliage) and water. You can either spray the plant or rub on soap with a sponge. Dislodge any scale as you go along and let the soapsuds sit on the plant a short while. After the treatment, rinse the foliage thoroughly because soap can clog pores. If you have more than a mild case of any of these pests, you may need a chemical solution from your garden center. In any case, as soon as you spot insects on a houseplant, isolate it and check all other plants thoroughly for a couple of weeks.