As the season shifts into a period of shorter days, Mother Nature brings forth bursts of bright yellow flowers to help in the transition. Because yellow is the brightest color of the visible spectrum, our attention is grabbed, whether the spots of color are found in the surrounding native habitat or planted intentionally in a cultivated garden spot. Yellow is a color of high energy, hope, cheerfulness, warmth, creativity, happiness and optimism. It’s a perfect choice for ushering in the fall.
Goldenrod is a genus of plants (Solidago sp.) of the aster family. Some species are already in bloom along the edges of U.S. Route 341 as one heads to Jesup, a road I traverse now several times each week. Over 13 native species of goldenrod can be found in Georgia. A close look at the blooms will reveal the distinct daisy head of ray and disc flowers. Goldenrods love sunny locations and can be found growing in the open areas of meadows, prairies, savannas and on the edge of woodlands, creeks, and the coastal salt marsh. The flowers are an attractive source of nectar for butterflies, bees, wasps and flies; the leaves are an important food source for foraging larvae of many different members of the butterfly family. Often accused of causing “hayfever,” goldenrod is an innocent bystander. Its pollen is sticky and transferred by insects. The actual culprit is the unassuming ragweed, a wind-pollinated plant with small greenish flowers growing along side the goldenrod. Its air borne pollen is the cause of irritation in the eyes, ears and throats.
Along U. S. 17, I often spot, the swamp sunflower (Helianthus angustifolius), found growing in the wetter areas along fresh water ditches, streams and low lying regions along the south and eastern states, particularly the coastal plains. This native perennial plant often reaches heights of five feet. The ray flowers are bright yellow and the center disc flowers are a darker brown. The two-to-three-inch flower is one of those cheery flowers that can’t help to bring out a smile. One plant usually produces up to 15 flowers. Because it is easy to grow, this plant is often cultivated for its flowers.
Not to be overlooked are the native cassia plants growing natively in sandy fields and open pine lands. Cassias are herbs of the legume family and are very closely related to two other members, Senna and Chamaecrista. Out at the farm where I now work, Partridge Pea (Chamaecrista fasciculata) is one of the forage crops growing in and around some 300 pecan seedlings that were planted this spring. All three of these plant genera are pollinated by bees in search of nectar and are also popular food sources for the larvae of several butterflies. Cultivated cassias are grown for ornamental purposes and make some of the most spectacular displays of yellow flower color in our area. The most outstanding specimen is Senna bicapsularis, a tropical-appearing tender evergreen legume with pendulous clusters of bright yellow flowers in the late fall. This cassia appreciates the heat and sun and grows best in climatic zone 9 and warmer. It can survive many years in our coastal zone 8 if planted in a protected location offering a warmer microclimate (as within a walled garden offering radiant heat and wind protection). There is much confusion in the trade concerning cassia plants and Senna bicapularis is often Senna pendula var. glabrata, a Category One Exotic Invasive. To avoid introducing such an invasive plant to our area, invest in one of these two natives such as: Bahama cassia (Cassia bahamensis, now Senna mexicana var. chapmanii or Privet cassia (Cassia ligustrina, now Senna ligustrina). Deer do love to browse on them, unfortunately.
One of the seven top perennials that students learn at The Ohio State University, my alma mater, is the bold chrysanthemum. It’s not a great perennial choice here as it tends to melt away in the heat of coastal Zone 9a summers, but many store fronts will soon offer a variety of beautiful blooming specimens at relatively inexpensive prices. Choose one that is mostly in bud and anticipate the emerging profusion of color. I always buy a few to strategically place in containers at the front door and on the back deck.
As the marigolds begin to falter in the garden after blooming profusely for months, you might consider introducing pot marigold (Calendula officinalis). This member of the aster family prefers cooler temperatures. The bright shades of orange and yellow flowers cheer up the garden. The flowers are edible and add pizzazz to the garden salad.
If you can still find it in local garden centers, celosia is an easy to grow, durable plant for fall. It is very suited for containers, borders and in the front of the garden beds in full sun. I have long propagated plants from seed so that I can have plants when they are considered “out of season”, and this is certainly an easy one to start from seed. Its color range extends beyond yellow into warm orange, scarlet red and a deep burgundy purple.
Yellow cosmos, Cosmos sulphureus, is a favorite of mine. Toss seeds into a lightly cultivated area, add enough rainfall or irrigation to get the seeds germinated and you will have season after season of these butterfly attractants. They will self-seed on their own.
I realize summer temperatures tend to drag into October for us and most of us look forward to cooler weather. But for those of you who are sensitive to shorter days, it never hurts to add a hint of autumn sunshine to the mix! You’ll feel better if you do.