Some of my very favorite garden plants are the true geraniums; aka hardy geranium, perennial geranium and cranesbill geranium. Ketzel Levine, author of “Plant This” and former Oregonian and NPR contributor, wrote that “hardy geraniums are like the movie extras without which towns would be deserted and parties would be duds. Hardy geraniums are wholesome garden inhabitants. They are familiar and therefore soothing, their faces an open book; you just can’t help wanting to trust the gardener who grows them.”

Why, you ask, is Liz writing about them now that the season is over with? The answer is simple. When I write about hardy geraniums in early spring, readers read what they think I have written and run out to purchase what I call the window-box geraniums, which are frost-tender and correctly should be labeled Pelargonium.

I have always been careful to differentiate between the two, with leaf and blossom descriptions as well as growth habits. Invariably I will receive a terse email chiding me for encouraging readers to purchase plants so early in the season that easily freeze. So much for communication.

I was encouraged to extol their virtues once again after reading an extensive article in the June issue of Fine Gardening on the trial testing of geraniums at the Chicago Botanic Garden in Glencoe, Ill. Glencoe is in USDA Zone 5b.

This time I decided to approach geraniums as a wintertime research project.

Then, come spring, there won’t be any doubt that you are purchasing a plant that will give you endless seasons of pleasure.

Richard Hawke, plant evaluation manager for the Chicago Botanic Garden is so convinced of their good traits that he decided to test 180 of the 300 species.

Hawke feels geraniums are simply awesome plants because of their beauty and tried-and-true reputation. However, he does admit to the fact that there are less-than-stellar varieties and he feels nobody wants to spend their money on a stinker. Over a trial period of 15 years, he has given the ratings of Excellent, Good, Fair and Poor to the test group.

The criteria used were their ornamental qualities, ease of growth, hardiness and disease and pest resistance. The growing conditions included full sun and dappled shade from trees. The care was minimal, allowing plants to thrive or fail under natural conditions.

Geraniums are well suited for our climate, with USDA Zone ratings of Zones 3 to 5. Geraniums are listed in the perennial section of our locally written “Xeriscaping in the High Desert,” available at the Oregon State University Extension Office in Redmond, and the frosting on the cake is that the plants are DEER RESISTANT.

I have some planted in mostly shade under juniper trees; others are planted in full sun. They aren’t picky. They don’t need a diet of fertilizer, can thrive with or without deadheading and, in many cases, new leaf growth can rise above spent flowers. Deadheading is advised to eliminate excessive reseeding.

Geranium flowers aren’t enormous. They have a wildflower charm, with a simple five-petal flower often displaying delicate veining of an additional color. The foliage can be an attraction in itself. The leaves are lobed and can range from bright green to gray-green. Some varieties show foliage of purple, bronze or yellow leaves. According to Hawke, many do not hold their foliage color throughout the season. The Victor Reiter strain loses its deep purple leaf color in midsummer but turns purple again in the fall.

Design suggestions include planting under roses to camouflage rose knees and complement the roses in color. They look especially good paired with contrasting textures like spiky iris. Hawke grows Rozanne with Mrs. Robert Brydon clematis (Zones 4-9) and says this sublime pairing is a hit for several weeks in late summer.

The varieties that made the Excellent rating in the trials include:

• G. macrorrhizum “Lahfelden”: height, 8 inches, with very pale pink blooms in mid-spring to early summer

• G. “Moran”: height, 24 inches, with violet-blue blooms from early spring to late spring

• G. “Orion”: height, 30 inches, with purple-blue blooms from mid-spring to late summer

• G. Rozanne (“Gerwat”): height, 20 inches, with purple-blue blooms from early summer to late fall. Rozanne won the 2008 Perennial Plant of the Year award as well as Royal Horticultural Society Award of Garden Merit. Although Rozanne had to settle for a rating of good in the trials, it is still considered as a top performer.

Maybe over the next few months we can convince our favorite nurseryman or woman to expand their selection of hardy geraniums. I think they are among the unappreciated and underused plants in our area. Spend some time over the next few months learning more about them and how they would serve a purpose in your landscape. You may have found an answer to a problem area.

Although not mentioned in the trials, our native Sticky Geranium (Geranium viscosissimum) deserves attention also. A word of caution might be necessary as it is considered a forage plant and the flowers may be palatable to deer.

Why are they called Cranesbill? It’s because their seed pods do somewhat resemble a crane’s bill.