Savannas and Woodland Edges in Early Fall.
I’ve showed you photos of Karen’s stunning spring savanna garden, but her autumn garden is equally notable.
Drummond Aster (Symphyotrichum drummondii) creates a sea of lavender-blue from late August to mid-November. Its daisies form a showy cylindrical panicle at the end of the 2-4’ tall stem clad in alternate, arrow-shaped leaves. Our most abundant blue aster, In nature it is found in savannas and woodland edges.
The asters are interspersed with White Snakeroot (Eupatorium rugosum), a tall-to 4’-, robust plant with large, toothed leaves, topped with clusters of tiny white button blossoms that bloom from mid-July through late October. Abundant, it livens up the late summer woodland.
Purple Giant Hyssop (Agastache scrophulariaefolia) also grew in Karen’s savanna, but I didn’t get a photograph of it. This picture was taken next to my garage at my house last year, growing with White Snakeroot, a stunning combination for shade.
The compact, cylindrical flower spikes are not purple, but, at best, a very pale lavender. It’s attraction lies, however, in its all over architectural look. Its height–from 3-6’–and its conspicuous large square stems add drama to the whole picture.
The brightest star of the shady garden in fall is Blue-stemmed Goldenrod (Solidago caesia). The upward-facing, tiny yellow daisies grow in the axils of the leaves; as the blossoms mature, the pointed lanceolate leaves hang down from the loosely arching, bloomy purplish-green stems from which it gets its name. This one-sided configuration makes the plant ideal for making wreaths–hence the other common name –Wreath Goldenrod. It spreads slowly by rhizomes, A shade plant, Blue-stemmed Goldenrod is found in woodlands, shaded dune slopes, shaded bluffs, and sandy Black Oak savannas. It’s not native to Kane County where I live; in the Midwest it is found in the far eastern counties of Illinois, throughout Indiana, and in most of lower Michigan.
It’s paired here with Brown-eyed Susan (Rudbeckia triloba), the last of the Susan’s to bloom, from August into October A branching perennial, it grows 2-4’ tall and around. A prolific seeder, you may find it in that perfect place you never thought to plant it. In nature it is found in partially shaded low ground or along woodland borders.
The more familiar Showy Goldenrod (Solidago speciosa) is also in bloom.
Its scepter of bright glowing golden flowers stands out in any garden. Long-blooming, it begins in August and doesn’t quit until the end of October. It is most at home in sandy Black Oak savannas near the lake, but will grow in oak savannas and prairies, as well. In my experience, it has not been long-lived in my sunny parkway garden where I first planted it, but it is thriving under the dappled shade of my rose trellis to where it migrated several years ago. Its bloom, however, faded a week or so ago.
The July blossoms of Goat’s Beard (Aruncus dioicus) have turned to feather dusters and add interest to the autumn picture along with the dried blossoms of Smooth Hydrangea (Hydrangea aborescens).
A carpet of various sedges, Wild Ginger, Sedum ternatum, Bloodroot leaves, and myriad violets grow under everything–every inch of ground is covered–a living mulch, a barrier to weeds and a defense against wind or water erosion and drought.
Wild Columbine (Aqualegia canadnses) makes an attractive groundcover, also.