What home gardeners should know about Spirulina and sorghum

Nearly 40 years ago, at Kibbutz Sde Boker in Israel’s Negev Desert, I spent a summer doing research on Spirulina. You may have heard of it. Spirulina has been called a wonder food since it’s dense in vitamins, minerals, and antioxidants and is noted for its anti-inflammatory properties. Its consumption is rising rapidly throughout the world with a market value set to reach a billion dollars over the next five years.

Spirulina was originally classified as a blue-green algae but towards the end of the 20th century was reclassified as a photosynthesizing cyanobacteria, although it is still popularly labeled as an algae. In any case, it lives in symbiosis with nitrogen-fixing bacteria, a physiology shared with legumes such as peas, beans, and lupines. As in the case of these edibles, Spirulina also has a high protein content.

At the kibbutz, we grew spirulina in large outdoor pools but now you can now grow it at home. Type “Spirulina growing kit” into your search engine and you will find several companies that provide everything you need to grow Spirulina in a fish tank-type apparatus, set up in your office or living room. Sprirulina can be eaten fresh or dried and turned into powder for addition to stews, soups, or smoothies. It can also be harvested for use as a garden mulch.

Algenair ( has manufactured an attractively designed lidded flask for your desk or kitchen counter where Spirulina is grown for air purification purposes. In addition to the removal of carbon dioxide and addition of oxygen that all photosynthesizing organisms provide, the Spirulina acts “synergistically with your home garden as the algae can be used as an all-natural organic fertilizer for your plants.” Incidentally, if you have seen green beer on St. Patrick’s Day, know that its color was produced by the addition of Spirulina powder to the brew. In China, various formulations of Spirulina wine are now imbibed.

Sorghum (Sorghum bicolor), whose growth habit will remind you of corn to which it is closely related, is another plant not customarily selected for cultivation by the home gardener. However, it is a magnet to pollinating insects and, thanks to its plethora of bronze flower tassels, provides an ornamental touch as well. Grass family plants such as sorghum are generally overlooked as pollinator plants yet their pollen and nectar are rich targets for honeybees, bumblebees, carpenter bees, and predatory beneficial insects such as parasitoid wasps and hoverflies.

Recent research also revealed that the aphid infestations regularly found on sorghum are a positive since the copious sugary plant sap or so-called honeydew excreted by aphids serves as a nectar substitute for many families of beneficial insects. The presence of aphids and their honeydew on sorghum may persist into months when other pollinator plants are no longer producing nectar; thus, sorghum may be a powerful force in keeping nectar-needy pollinators in the garden.

If you had any doubts about the capacity of lilacs to bloom in a mild climate, the following testimonial from Patti Hugh, who gardens in the balmy coastal community of Huntington Beach, should put those doubts to rest. “I have had a lilac tree in my home for over 20 years and I love it,” she writes. “It kind of does its own thing as long as I keep watering it. Right now, it is about to burst into leaves and blooms. It blooms several times a year instead of all at once. The blooms are lilac-colored and smell heavenly. Our tree was purchased at a small single-owner nursery that had lots of unusual plants. The owner was a special lady who really knew her plants. My lilac was the only kind she had and was adapted to this area. It is special to me as I remember lilacs from the Chicago area which made spring a wonderful time of the year.” The variety to which Ms. Hugh refers might be Lavender Lady, since it has a solid reputation for blooming in Southern California.

Ms. Hugh also had a question concerning her lemon tree, asking me to “come up with a solution for getting rid of whatever is peeling my Meyer lemons, eating the peel and leaving the flesh in the tree for the bugs.” The lemon-peeling critter involved in this debacle is most probably a rat, but could also be a mouse (or mice), and possibly a possum. There are two solutions to this problem. Either cover your fruits with some sort of protective covering such as QYFIRST fruit protection bags or neutralize the critter by trapping it.

In response to a recent column on dwarf citrus trees, Nancy Terrebone, who gardens in Encino, wrote about her large collection of productive dwarf specimens as follows: “I have had dwarf Valencia and navel orange trees in pots for over 25 years. My Meyer lemon of the same age looks weak but it still produces at least 25 lemons twice a year. I transplanted these three trees into larger pots about 10 years ago and pruned their roots at that time. My potted semidwarf Mexican lime and semidwarf grapefruit are five years old and both produce a lot. I have a potted three-year-old dwarf Cara Cara (red-fleshed navel orange) and Meyer lemon of the same age that are very productive. I also have a semidwarf grapefruit growing in the ground that took seven years to produce. I use Dr. Earth organic fertilizer one or two times a year, in spring and sometimes summer. In winter, I water, at most, once a week and, in summer, sometimes up to two times a week.”

California native of the week: White alder (Alnus rhombifolia), properly sited, is one of the most glorious California native trees. I say properly sited since, although it adapts to drought, it would much prefer a riparian habitat, or at least a soil that is somewhat moisture retentive. Where it is regularly watered and has good light on all sides, it grows into a handsomely symmetrical, almost cone-shaped specimen that you will swear is the most verdant tree you have ever seen. Perhaps it owes its verdure to the fact that it lives in symbiosis with nitrogen-fixing bacteria so that it is never deficient in nitrogen, the main constituent element of the chlorophyll molecule that makes plants green.

Ceanothus is another nitrogen-fixing plant and perhaps that explains its brilliantly verdant foliage as well. White alder may grow over 50 feet tall so you will probably have to prune it once in a while unless you live on a large estate. I may also be drawn to this plant because my namesake birds, the pine siskins, consume its seeds, as do its goldfinch cousins. Alas, in the typical manner of trees that grow quickly, alders do not usually live longer than a hundred years and often meet their end much earlier.  White alder bark is pleasantly gray in color and is fully revealed after the leaves of this deciduous species have fallen.

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