By Penny Pawl, UC Master Gardener of Napa County
I have been checking the Farmer's Almanac and other sources like the National Weather Service to try to predict what kind of weather we will have this coming winter. Will it be almost flooding, downpours, freezing or a drought?
According to the Farmer's Almanac, we can expect downpours in November. What to do with all that rainwater? If left to drain into the gutters and storm drains, it just goes back out to sea with many pollutants.
If you build a rain garden, you can divert the water to a location where it can drain back into the soil and be purified at the same time. You can collect rain water from your gutters, rooftop and sidewalk and from the roads. You can collect many acre-feet of water.
For your rain garden, choose a low spot in the yard where water gathers during heavy rains. By enlarging this area and getting it ready for the rainy season, you will conserve a precious resource and use it to make an attractive area in your garden. Many rain-garden plants take little care once established, and their blooms attract pollinators and other good bugs.
Once you have identified the best area for your rain garden, you will need to remove whatever is growing there and lower the elevation by 12 to 14 inches. If your soil drains slowly, put in some type of plastic pipe and gravel in the bottom to help it drain. Add compost and sand to improve drainage. Mix these amendments well with the native soil so that water will drain in 48 hours or less. The plants will help take up the moisture. As with swales, the ground underneath will collect water and keep your plants going during dry seasons.
Once you have the soil prepared, select the plants for your rain garden. You may also want some garden accessories, like a stone or wooden bridge to cross a damp area. There are so many good ideas online that I want to make another rain garden for myself.
Sunset's Western Garden Book has a whole section on water gardens and good plant choices. Some of the recommended plants bloom; others have attractive leaves. Iris will grow well along the edges of the rain garden. Some native grasses also thrive in that environment, as do many ferns. Your rain garden could well become the focal point of your landscape.
If you choose native plants, you will not have to fertilize. These plants evolved in our soils and can get the nutrients they need. Once established, they will need much less water in hot weather as their roots go deep in the soil.
Visit local nurseries to see what they have for rain gardens. You can also do research online or consult books on the subject. The Napa Valley chapter of the California Native Plant Society will have its annual plant sale on Saturday, October 7, and Sunday, October 8, from 10 a.m. to 4 p.m., at Skyline Wilderness Park in Napa. You'll find a selection of native plants that would be excellent for your rain garden.
A lawn can be beautiful with lots of water, fertilizer and herbicide. How much more exciting and environmentally friendly to install a rain garden and make your landscape unique.
Do you want to become a UC Master Gardener of Napa County volunteer? To obtain an application, you must attend an information meeting. For dates, location and times, or to learn more about the program and volunteer commitment, visit the UC Master Gardener of Napa County website.
Workshop: UC Master Gardeners of Napa County will host a guided walk and talk on “Pollinators, Native Plants and Beneficials” on Saturday, September 23, from 9:30 a.m. to 11:30 a.m. at the Martha Walker Garden at Skyline Park in Napa. Any discussion of pollinators would not be complete without some remarks on the bounty of beneficial insects found in everyone's garden. Come see if you can recognize some pollinators and beneficial insects. Online registration (credit card only); Mail-in form (cash or check only)
Master Gardeners are volunteers who help the University of California reach the gardening public with home gardening information. U. C. Master Gardeners of Napa County ( http://ucanr.edu/ucmgnapa/) are available to answer gardening questions in person or by phone, Monday, Wednesday and Friday, 9 a.m. to Noon, at the U. C. Cooperative Extension office, 1710 Soscol Avenue, Suite 4, Napa, 707-253-4143, or from outside City of Napa toll-free at 877-279-3065. Or e-mail your garden questions by following the guidelines on our web site. Click on Napa, then on Have Garden Questions? Find us on Facebook under UC Master Gardeners of Napa County.