Nothing says summer like geraniums.

That said, it’s fall now, and our tender geraniums (the fleshy perennials that belong to the genus Pelargonium) are showing their age. The very popular Pelargoniums are native to South Africa, so it’s only natural that they would find our cool and damp fall a bit unusual. They show their discomfort in leggy growth, few flowers and otherwise general unruliness. Unlike the smaller, wild, hardy geraniums in the genus Geranium, which are common to North America and Europe, Perlargoniums look as if they would like nothing better than to fly south for the winter.

Fear not. There are several ways to over winter or keep your Perargoniums.

Just to make sure we’re talking about the same perennials, here are some common Pelargoniums.

Common garden geraniums, also called “zonal” geraniums. These are sold as bedding plants, they are compact in habit and often have fancy leaves marked by distinct bands – or zones – of darker pigments, tri-colored leaves or leaves with silver or white markings. Flowers may be single or double, are clustered into heads, and may range from red, pink, and salmon to white.

Lady, regal or Martha Washington geraniums. These beautiful large-flowered types thrive in the Pacific Northwest, since they require cool (50 to 60 degree) night temperatures in order to bloom. They don’t do well in climates where evenings are warm, such as the Midwest.

Ivy-Leaved geraniums. These have vinelike growth and smooth, leathery leaves and flowers with narrower petals. They are popular in Europe, often planted in window boxes. These look good in hanging baskets.

Scented-leaf geraniums. These scented plants have a wide range of leaf shapes and are used for making potpourris, sachets and tea flavorings. They make excellent houseplants, and many have soft, finely textured foliage and small flowers. Scents include rose, lemon, nutmeg, apple and peppermint.

Geraniums are generally care-free garden performers. They need at least six hours of full sun each day for best growth and flowering. In the hottest part of the summer, they do better in afternoon shade. Out in the garden, space plants eight to 12 inches apart in rich garden soil. Fertilize every two weeks, and water when soil feels dry to a depth of two inches. Remove old flowers to keep plants looking fresh.

If you keep geraniums in containers, select a pot that has drainage holes in the bottom or sides. Plant them in an ultra light weight potting mix, with plenty of peat and vermiculite so you’ll have an easy time changing the positions of containers. Geraniums need good drainage. Avoid using a saucer under the container. Allow water to fully drain from the pot.

With relatively few pests, geraniums can fall prey to a few diseases, such as Botrytis, a fungus that occurs when days are warm but nights are cool enough to create dew. Diseased blossoms will look moldy, turning brown and mushy. It spreads quickly, so remove and discard affected blooms or plants. Also look out for geranium budworm, a tiny caterpillar that destroys the bud from within. The best treatment is to handpick the eggs and worms. Check for budworms daily.

To overwinter your geranium, either take cuttings in the fall and keep the small, potted plants on a windowsill with a bright, sunny southern exposure during the winter, or dig them from the garden before the first frost and plant them in pots large enough to accommodate the roots. Cut the plant back to six inches tall, and place in a sunny area such as a heated porch.

Some people overwinter geraniums by digging the plants before the first frost, knocking the soil from their roots and hanging the plants upside down in a cool, moist basement with 80 percent humidity and temperatures between 35 to 45 degrees. If plants begin to dry out, soak the roots in water a few times each winter. In spring, take the plants down, cut off half to three-fourths of the top growth and replant outdoors.

Don’t bother overwintering your geraniums if they are diseased or are infested with pests. It’s best to trash them and begin again with new, healthy starts the next year.

Cathy Peterson belongs to the Clatsop County Master Gardener Association. “In the Garden” runs weekly in Coast Weekend. Please send comments and gardening news to “In the Garden,” The Daily Astorian, P.O. Box 210, Astoria, OR 97103 or online at peterson@pacifier.com

CORVALLIS – Since its first publication more than 50 years ago, “Trees to Know in Oregon” has become the most requested publication from Oregon State University Extension Service.

Recently revised and republished, the little spiral-bound book makes a great stocking stuffer for hikers, gardeners and armchair naturalists. It combines identification and anecdotes with maps, photos and line art.

According to the book’s authors, Oregon is home to more than 50 national champion trees listed in the American Forestry Association’s National Register of Big Trees. They include the nation’s largest black cottonwood (370 feet), black walnut (278 feet) and garden plum (a 47-foot giant more than 10 feet around).

The 128-page book is full of tidbits to help you get to know Oregon trees. For example, the authors point out that lodgepole pine was first named by Lewis and Clark. They describe how whitebark pine and Clark’s nutcrackers are almost totally dependent on each other for survival. And they note that, although more than 1,000 varieties of pears have been named, only a half-dozen varieties are grown commercially.

To order “Trees to Know in Oregon,” EC 1450, visit the OSU online catalog, eesc.oregonstate.edu/agcomwebfile/edmat. Or send a check or money order for $12 to Publications Orders, Extension & Station Communications, Oregon State University, 422 Kerr Administration, Corvallis, OR 97331-2119.