The Backstory Some couples just look good together. So it is with golden California poppies and purple lupines. Poppies and lupines constitute a classic wildflower combination for gardeners as well as for artists! In fact, the colors of the University of California, blue and gold, were chosen because the fields around the first campus (in 1868) reportedly were replete with blue lupines and golden poppies. (A few years ago, a hillside in north Livermore was also covered with lupines. It was a glorious site! Now it is covered by a parking lot, albeit with solar collectors above. I guess this is one form of progress.) Last year, a single purple lupine (Lupinus succulentus) found its way into the woodland section of the Granada Native Garden. This year, its progeny are spreading themselves around among the poppies (lupines may do better when they self-seed than when we try to help them). Hopefully this display of color will become a regular annual attraction at the Granada Native Garden. Lupine (also spelled lupin) comes in other colors besides blue and purple, such as yellow and shades of red or pink. Lupine is also frequently planted along road cuts; this Spring there was a good show of yellow lupine along the widening and re-alignment of Rt. 84/Vallecitos Rd.
A Case of False Incrimination Lupines are strikingly pretty Spring flowers. Aside from that, the name “lupine” comes from the Latin “lupus”, which means “wolf”, because lupines grow in deficient, low-nutrient soil, and they were (incorrectly) blamed for the low quality of the soil! In addition, the interesting shape of the leaves (several slender leaflets radiating outward from a central point, aka “palmately compound”), and covered with soft hairs in some species, might have reminded some people of a wolf’s paw. (But this is just my theory.) Actually, lupines are legumes (members of the pea family), and like most of the members of that family, their roots have nodules that contain a very special bacterium, Rhizobium (as in the photo on the right). These bacteria are able to convert atmospheric nitrogen into nitrate, a form that can be absorbed and used by the plant. For that reason, legumes are commonly planted as a “green manure” crop in order to renew the nitrogen content of the soil in a garden. (This is done by planting the lupine in the desired location, then digging it in or plowing it under while it is still green or after flowering.) So rather than depleting the soil, lupines actually restore it, especially for growing crops that have a high nitrogen requirement, such as cucumbers, squash, broccoli and spinach. Some species of lupines are named bluebonnet, because the shape of the flower petals is said to resemble the bonnet worn by pioneer women to shield them from the sun.
Edible or Not Edible? Like other legumes such as peas, beans, peanuts and soybeans, lupine seeds are a good source of protein, containing all of the essential amino acids required for complete nutrition. However there are more than 100 species of lupine identified in California, and they vary in terms of their suitability for food. The seeds of some lupine varieties contain toxic alkaloids and isoflavones which can be dangerous to livestock, especially sheep. And like peanuts, lupine seeds may cause an allergic reaction to those who are allergic to peanuts. The juice in the leaves and stems may be a notable skin irritant. In spite of this, lupines constituted a significant part of the Native American diet. The toxic components were removed from the leaves and seeds by boiling, as was the practice with many other plants that contain toxins. Quail are especially fond of the seeds, and lupines are an important larval food for some local endangered butterflies, such as the Mission blue and Lange’s metalmark. Notice in the photo at the left that the flower of the lupine becomes fruits that resemble pea pods, typical of plants that are in the pea family (Fabaceae). (You can enlarge the photo by clicking on it.)
PostScript The showy display of color we usually expect at the beginning of Spring – the blue and purple and white California lilacs, the magenta redbud (also a member of the Faba- ceae), and the yellow flannelbush – seems to have been short-lived this Spring. My guess is that the relatively dry Spring we have had is responsible. And the lupines too! Maybe this is going to be the new normal.
Quote du Jour “I wish I could awaken through some magic of the written word a desire for wildlife conservation among those who care not about it.” Raymond F. Dasmann, The Destruction of California, 1966
Granada Native Garden, 801 Murrieta Blvd., Livermore, CA 94550 http://www.granadanativegarden.wordpress.com