Sunflowers are the exuberant darlings of the summer garden, and you can still plant them in August.
No garden edible grows at a greater rate than the sunflower. Certain varieties take only two months to go from germinating seed to full-blown flower, reaching a height of ten feet. Such quickly growing, albeit shorter, varieties do not make pollen and will not produce seeds, but their blooms will reach 4-6 inches in diameter and stay fresh in vase arrangements for up to two weeks. One such variety is Zohar, advertised as needing a mere 50 days from seed planting to flower harvesting. Although they don’t yield seeds, pollenless sunflower petals are edible like those of all sunflower types, ranging in taste from slightly sweet to slightly bitter.
Seedless sunflowers arose as a mutation 1988. The cut flower industry was ecstatic with this development since typical sunflowers shed pollen, making them unsuitable for vase arrangements, since they would shed on carpets, furniture, and tablecloths. Florists also proscribed the use of sunflowers in bridal bouquets since what bride wants to see yellow stains on her wedding gown? Another advantage of pollenless sunflowers is that they stand up straight as opposed to conventional sunflowers that flop. Pollenless sunflowers still produce nectar so that pollinating bees and other insects will still seek them out as a source of sustenance.
Even conventional sunflower varieties that may take up to four months to ripen their seeds may be planted now or, for that matter, at any time of the year. As long as the seeds are planted in a warm garden spot, they may germinate, regardless of the season. Their development will be arrested by cool weather, but they are likely to grow to their full potential eventually.
You cannot germinate roasted sunflower seeds, but those that are raw and still in the shell — even when packaged as a snack — will sprout and those from birdseed feeders falling on the ground, may sprout too. Before planting sunflower seeds, make sure they imbibe enough water to germinate by soaking them in water for 8-12 hours. Plant them 1-2 inches deep and keep the soil, which must drain well, moist. Sunflowers do require regular water during germination, early growth, and when flowers form, but become more robust as they mature. Once seeds have begun to form, watering frequency can be reduced, and irrigation may be eliminated entirely.
If you detach a sunflower for a vase arrangement, cut the stem at an angle and place it in a tall vase. Before placing the stem in water, make sure to remove all leaves that would be submerged. Leaves under water, on any cut flower stem, are likely to be smitten with water mold that shortens the life of the flower above. The sunflower’s greatest enemy is desiccation, so make sure that its water supply in the vase is regularly replenished.
Sunflowers are native to America’s Great Plains. In the 1540s, Spanish explorers first brought their seeds to Europe. In the 1880s, Van Gogh famously painted them in Arles, France. Most of the sunflowers on Van Gogh’s canvases are a mutant double-flowered type. Their pom-pom heads resemble chrysanthemums, which are sunflower cousins. The seeds of Sungold, a double-flowered variety that could have stood in a vase in Van Gogh’s studio, are widely available through Internet vendors. There is a plethora of pollenless varieties available as well, with colors that include yellow, orange, red, burgundy, lime green, and white, as well as bicolored varieties.
The sunflowers that were first grown in Europe were used primarily for ornamental purposes, with their seeds consumed almost exclusively for medicinal, anti-inflammatory effects. Two hundred years would pass before the sunflower came into its own as a commercial crop for its food and oil value. This development, as it happened, was religiously inspired. In the early 1700s, the Russian Orthodox church issued a decree banning the use of butter, lard, olive oil, and a variety of other fats and oils during the 40 days of Lent. Since sunflower seed oil was not banned by the decree, farmers began to grow sunflowers to supply the need for cooking oil during Lent. Slowly, land was turned over entirely to sunflowers so that, by 1800, there were two million acres planted to sunflowers in Ukraine and Russia. Eventually, two major strains of sunflowers developed, based on their seeds either being eaten whole or used for oil. Healthwise, cooking oil made from sunflowers is the preferred vegetable oil due to its unsaturated fats and, especially, its oleic acids that help increase good (HDL) cholesterol.
Several people emailed wanting to know the precise procedure for applying mineral oil to silks of sweet corn in order to prevent earworms, which are actually moth larvae, from causing damage. Perform this task when silks have begun to wither and turn brown, approximately five days after the silks emerge. Use 1/2 to 3/4 of an eye dropper of mineral oil (whether horticultural or medicinal) per plant, applying it directly to the mass of silks at the tip of each ear. The oil suffocates the newly hatched larvae.
Bee hotels are designed to attract solitary native bees that can make a significant contribution to pollination in your garden. They consist of a collection of tubes nestled cheek by jowl in a structure similar to a birdhouse and are available from online vendors for $10-$30. You can also make your own bee hotel by attaching a piece of 2 x 4 wood to a structure or fence, 3-5 feet off the ground, and drilling holes half way through the wood. The diameter of the holes should range from 1/8” to 1/2” since our native bees vary in size, depending on the species. The advantage of using tubes for nests is that they can be cleaned annually, a procedure needed to prevent bee pathogens from entering your bee hotel.
California native of the week: Canyon sunflower (Venegasia carpesioides) is an irresistible, shade-tolerant perennial selection. Its bright green foliage, uncharacteristic of most California natives, complements glowing, butter yellow blooms. It has ground cover stature when young, yet may eventually reach several feet in height and, atypically for natives, can grow in clay soil, too. You will find canyon sunflower blooming in the Santa Monica mountains between February and September, depending on available moisture. This is a pioneering species after a fire so it should be found proliferating in areas that were burned by our recent wildfires.