Published: 09/23/2022 16:05:19
Modified: 09/23/2022 16:04:40
Many gardeners go to the nursery in June and buy blooming things for their garden – and rarely come back until next year. But that means they have few flowers left in bloom now that summer is drawing to a close. Not me. I buy perennials at any time of the year. Fall flowers are not only important to me, but also to the monarch butterflies, which need to eat plenty of hearty meals before flying to Mexico.
Many of the flowers that bloom in the fall are large wildflowers that have been tamed and made into garden flowers: many of the Autumn Asters, Joe Pye Weed and Rudbeckias (Black-eyed Suzanne) sold in nurseries have just been selected and bred to be more ‘garden-worthy’.
According to expert entomologists, the best plant for fall pollinators is goldenrod (Solidago spp.). This great beauty has a bad reputation in some circles, as some species of goldenrod are somewhat aggressive, arriving uninvited and spreading madly through roots. And since they have massive root systems, they are not easy to remove. But not all are like that, and some are sold in nurseries.
One of my favorite goldenrods is “Fireworks”. I’ve had it for about 10 years and it’s not a racket at all. The original facility has grown each year, but never to the point of causing problems. It blooms in September with dainty yellow flowers in a vase-like arrangement. It is readily available in nurseries. It stands three to four feet tall.
I also grow what’s known as a blue-stemmed goldenrod (Solidago caesia), a shade-loving tiny goldenrod that I purchased many years ago at Garden in the Woods in Framingham, Mass. It’s perfectly well-behaved: it stays in a neat clump and blooms late in the fall. It’s only about 16 inches tall.
New York Ironweed (Vernonia noveboracensis) is a great pollinator plant, standing 4 to 6 feet tall or more with purple aster-like flowers in large clusters. It thrives best in full sun and moist soil. Because it is such a tall plant, it is recommended that you prune it back to the ground in early summer when it is 60cm tall to maintain a more manageable size. I wouldn’t do that until my second or third year. And don’t give it fertilizer at planting time or it may flop. Monarchs love this plant, as do countless bees.
New England asters (now no longer with the scientific generic name Aster, but Symphyotrichum) come in many sizes and some colors. The savages are great. I have them next to my creek in a light lavender. But commercially available ones also come in pink and purple. They vary in height from being quite short (often sold in bloom with the chrysanthemums) to over 5 feet tall. The mother-sized grow taller in the second year and beyond as they are cut back periodically to increase the number of blooms and keep them short. Full sun is best for these; They grow in normal garden soil.
Joe Pye weed (Eutrochium spp., formerly Eupatorium) is also loved by monarchs and pollinators of all kinds. Native Joe Pye grows wild by my creek, but I also grow it in a garden bed I call the “Darwin bed.” The Darwin bed is never weed, and large flowers fight for space. This bed includes Joe Pye, Turtle Head, Asters, Goldenrod and Giant Fleece Flower, among others.
The variety in the Darwin bed is called “Gateway”. Instead of greenish stems, it has dark purple-black stems and grows even taller than the native species. Mine is nearly 8 feet tall and grows in moist, rich soil. All species have pink to purple flowers in large racemes at the tops of the stems, sometimes a foot or more across.
There is a smaller version of Joe Pye Weed, one called “Baby Joe” that was bred smaller, reportedly 2 to 3 feet tall. But I hear it’s closer to 3 to 4 feet if you’re happy with its location. All have very stubborn root systems, so plant them where you want them.
One of my favorites is loved by bumblebees, but nectar and pollen are unavailable to monarchs because the flowers are tightly closed. Turtlehead (Chelone lyonii) has clusters of delightful pink flowers on 4-foot stalks. The flowers are unlike anything else I grow. They resemble a turtle’s head, and bumblebees enter through the turtle’s “mouth.” If you listen, you can sometimes hear the bees inside – almost growling. Or do they purr? I do not know.
Turtlehead has a long flowering period and makes a great cut flower. They start blooming in August and bloom well into September. They do best with rich, moist soil, but I have them in full sun as well as full shade. There is another turtle head that is white but much less powerful to me. Its Latin name is C. glabra and I have rarely seen it for sale in a nursery.
A real joy for me is to have a few bulbous plants that bloom in the fall. The autumn crocus is actually not a crocus at all, but a species known as Colchicum autumnale. It has leaves in spring that disappear in summer, then surprises us with large crocus-like flowers on 4-inch stalks. The flowers occur solitary and filled in colors from white to pink to purple. Expensive but worth it. Most reliable in zone 5 or warmer, although I have it in zone 4. The flowers stand on dainty stems and often fall over unless planted in a ground cover like Vinca that will help hold the flowers up.
So go to your nursery now and see what you can bloom in the fall. Our pollinators also need food now.
Henry Homeyer is a garden consultant and lifelong organic gardener. He is the author of four gardening books. You can reach him at [email protected]