by Leslie Duthie, ELA Publications Committee Chair
There are plants that appear in my garden that I did not personally plant. Weeds? Maybe. It might depend on your perspective. As a gardener with a strong leaning towards native plants, I love when plants naturally spread from garden to garden, popping up in new and unexpected places. Occasionally a plant will just appear—it’s not planted, it’s not from another garden, it’s not even on the property. Some are truly weeds and often invasive, like bittersweet (Celastrus orbiculatus), mugwort (Artemesia vulgaris), or dame’s rocket (Hesperis matronalis). These all grow in my landscape and I remove them upon discovery.
There are ‘weeds’ that I leave, however, because I find them to be charming additions to the garden. Violets (Viola sororia) fill spaces in the lawn, at the borders of gardens, and among other plants. They serve as fillers with pretty flowers in spring as well as weed suppression. Violets serve as a larval host for over 30 species of butterflies and moths, and are the primary food for the Fritillary butterflies. Hairy beard tongue (Penstemon hirsutus), a favorite planted in my garden, is now taking over a section of lawn, growing in cracks in the driveway, and along the foundation, which I find delightful. The biggest array of my ‘weeds’ arrive in fall. Fall asters, often considered weedy, offer tremendous value in terms of beauty and ecological value. These late-season blooms extend visual interest in the garden, particularly the small-flowered ‘frost asters’ that last until the very end of the season. Migrating song birds rely on the oil-rich seed of asters (and goldenrods) in order to complete their trip south. Before you pull, maybe give these plants a second thought.
Wood aster (Eurybia divaricata)
White wood aster (Eurybia divaricata) is one of my top ten fall asters. I love it because it spreads slowly and forms a colony in random corners of the yard. I allow plants to fill in shady or forgotten corners of the yard so that there is less lawn to mow and more habitat for wildlife. Shorter than many species at two feet tall, it creates a swath of large white flowers that are a delight when other plants are subsiding. I have interplanted it among a large patch of violets providing flowers when the violets are long past their prime. It thrives in average garden soils in full shade while tolerating some sun. A worthy garden perennial!
The most common aster currently in my garden is the blue heart leaf aster (Symphyotrichum cordifolium). It is three to four feet tall and a bit unruly looking, but the clusters of small purple flowers that appear are gorgeous late in the season when the perennial border can endure a little disorder. Plus, this little flower provides ample nectar for the remaining bee and butterfly species around in late fall.
Calico aster (Symphyotrichum lateriflorum) Photo by Dan Jaffe Wilder
Two other small asters that are worthy of space in the garden are small white aster (Symphyotrichum racemosum) and calico aster (S. lateriflorum). Sometimes difficult to tell apart, these two small-flowered plants produce copious numbers of white-petaled flowers in mid to late fall. The small white aster is a bit taller and has narrow, linear leaves, while the calico aster has broader leaves and gets its name as the disk flowers (in the center) change from yellow to rosy purple as the flower matures. Its varying shades of yellow, pink, and purple are reminiscent of calico cloth, hence the common name. Asters as a group are important to many species of caterpillars of butterflies and moths including the charismatic brown headed owlet caterpillar.
Smooth aster (Symphyotrichum laeve), can also be a bit gangly due to its height, up to six feet, but the flowers are large by aster standards. The petals are long and purple with a stunning center of yellow disk flowers. This plant does best in full sun where it is likely to produce many more flowers, but I have seen it along shady roadsides and garden edges where it still shines in all its tall glory.
Despite their bad rap as garden thugs, goldenrod is also a keystone species, critical to an abundance of wildlife, so some are worth a second look. A goldenrod for shade is the blue-stem goldenrod (Solidago caesia). This lovely plant forms clumps of arching purple-blue stems that allow the axillary clusters of bright yellow flowers to stand out. It thrives in full shade where it stays a bit more compact. You will also find it in sunnier locations as a more robust plant.
Blue-stem goldenrod (Solidago caesia)
Zig zag goldenrod (Solidago flexicaulis) has some unique qualities that I find desirable in the garden. I planted this in a meadow garden and a perennial border—it was slow to take off, but now it is appearing in other garden spaces, slowly creeping in borders and edges. Its bright yellow flowers are a sunny addition to the fall garden. Goldenrods are also a key larval host for numerous butterflies and moths and the seeds attract a variety of song birds.
The next time a ‘weed’ sprouts up among your perennials, maybe it will be something fun and interesting like those noted above. Weeds are a part of gardening, but they can also be amazing additions to both garden and lawn spaces.