|Coast Sunflower (Encelia californica): photo by Cliff Hutson|
The drought in California over the past five some odd years, and the resulting restrictions on watering, have been rough on home gardens, public plantings, and native plants. However, one plant that has been holding its own, at the botanic garden where I work, is one of the sunflowers.
Helianthus annuus, the common sunflower, is an annual herb that is native to California and is also found elsewhere in North America . Sunflowers belong to the what is probably the largest family of flowering plants - the Asteraceae (or Compositae). The name sunflower may derive from the impression that the blooming plant appears to slowly turn its flower towards the sun as the it moves across the sky, or from the shape of the flower which resembles a child’s drawing of the sun.
Sunflowers do display heliotropism in the bud stage. The motion is created by special cells in a flexible segment of the stem just below the bud. However, mature sunflowers become fixed in an easterly direction, with only their leaves continuing to track the sun. This motion, from east to west, is believed to increase photosynthesis.
The term Compositae, i.e., composite, comes from the fact that the “flower”’ is actually composed of many flowers. The flowers on the outer margin are ray flowers. The flowers at the center of the head are the disc flowers, which will mature into seeds. Many sunflowers are beautiful ornamental flowers in an annual bed or a mixed border. They attract bees and are also a good choice for butterfly gardens; monarch butterflies are especially attracted to sunflowers.
“Claremont Sunshine” Sunflower
|Claremont Sunshine: photo by Cliff Hutson|
RSABG is home to a cultivar of Helianthus annuus, “Claremont Sunshine”, the plant that is doing pretty well. Cultivars are bred from exceptional plants of an existing variety because they possess a desired attribute. I read that Bart O’Brien was driving on I-5 and spotted some wild sunflowers that were a very pale yellow, instead of the golden color. So he marked the spot, came back and harvested the seeds, then cultivated them.
The Fall Planting Festival at Grow Native Nursery will showcase this and thousands of other California native and water efficient plants on October 1, 2016, 10 am - 4:30 pm - Members only, 8 -10 am.
Rancho Santa Ana Botanic Garden has been selling California native plants since 1978. So, , if your are in Southern California, don’t miss this ideal opportunity to purchase hard-to-find, one-of-a-kind natives and to get your gardening questions answered by friendly, experienced botanic garden professionals and volunteers.