Some perennials are built to take some frost while in bloom. Others collapse at the first brush with cold temperatures, no matter how short the duration. It is wise to keep some cardboard boxes handy for temporary protection.
 Dicentra |
Bleeding hearts (Dicentra) are among my favorite backbone
plants for the shade garden. If you grow a selection of the
everblooming species and hybrids, blooms will be produced from
late April through the first hard freeze. To keep them blooming
over such a long period, plant in soil high in organic matter and
mulch them. Deadhead as you walk by so energy does not go into
seed production. Do not let them severely dry out during the dog
days of summer. Just provide good basic care.
Our native species D. eximia and its cultivars are my favorite, followed by the native D. formosa from the western U.S. Consider beginning with a drift of at least 3 plants of D. eximia for pink heart-shaped flowers and fern-like foliage. 'Snowdrift' is quite lovely with pure white hearts over foliage with a bluish overlay. 'Luxuriant' has cherry-red blossoms and can be a cultivar of either D. eximia or D. formosa, depending upon what nursery catalog you are shopping. |
Probably the second most common misconception I hear concerns the lack of perennial plants with attractive blooms for late summer and fall. There truly is no shortage of reliable plants, just a lack of emphasis in gardening literature. The selection may not be quite as abundant as spring and early summer blooms, but there remains quite a show that can be presented in the late season perennial garden.
Corydalis is related to Dicentra, very much resembling the plants in foliage. There are two species of Corydalis I am very fond of in my garden and I depend upon their color from April through hard frost.
| Corydalis lutea, or European yellow corydalis, is a workhorse when given the same environment as the everblooming Dicentra. The species has deep green rounded fern-like foliage with bright, butter-yellow, drooping clusters of blooms. It will seed and form a gradually spreading drift. |  Corydalis lutea |
My other favorite is for an opposite environment of dry, rocky, shade. The yellow-white corydalis (C. ochroleuca) thrives with blooms of white with one yellow lip in difficult spots where little else will grow . It, too, will spread by seeds into rocky places to form drifts of color from late April or early May through November or December. |  Corydalis ochroleuca |
Fall blooming anemone begin bloom around mid-September come into full flower during October and, weather dependent, remain in flower during November.
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Two species and their cultivars, along with many hybrids offer
several selections of fall blooming anemones. A. hupehensis
will usually show up as cultivars named 'Praecox' and 'September
Charm'. The first is purple-pink, the latter a bright purple-pink.
A. hupehensis var. japonica appears to have double
flowers due to several small sepals.
A. hybrida is a cross with the two above species and A. vitifolia. Under the heading of A. hybrida you will find numerous selections for open shade. While the fall blooming anemone may be somewhat slow to settle in and bulk up when transplanted, be advised that these plants need room. If you do not give them room when planting, they will take what they need at a later date. |
 Anemone 'Praecox' |
Two of the most well known fall blooming genera have not been mentioned. Hosta is a non-native that has become a backbone plant of almost every shade garden in North America. While hosta are noted primarily as a foliage plants, I happen to enjoy their blooms. You can have blooms from June through October by asking about bloom period at the nursery while making a purchase. The hummingbirds will thank you as well. I find hosta blooms are a favorite of the hummingbirds who visit my gardens.
Blooms can be a pure, glistening white to lavender and purple. Shape can range from stars to inflated tubes or flaring trumpets. Some have wonderful scent. There are breeders of hosta working on bloom size, color and shape, enhancing the selections of the near future.
October is the month when truly spectacular foliage comes into show for the garden. There are so many wonderful possibilities, but there is only room to mention two of my favorites.
If you have not grown our native Amsonia in your garden, a truly great plant is being neglected. There are quite a few species with different heights, spread, foliage and varying appearances. They share the same faded-bluejean colored blooms, thus the common name of 'bluejean flower.' All species I am aware of have foliage turning a bright gold in the fall.
 Amsonia hubrechtii |
My favorite to date is the Arkansas bluejean flower
(A. hubrechtii). About three feet in height and four feet in
diameter, it performs best where it can receive plenty of light,
such as a western woodland edge or meadow. Foliage is narrow and
thread-like giving a delicate, airy, appearance. Amsonia
die back to the ground each winter to a woody rootstock. There are several hardy geraniums having foliage that turns from green to attractive colors in late fall. My favorite thus far has an almost impossible to pronounce name. Geranium wlassovianum (no common name) has hairy grayish-green foliage and magenta-purple flowers with prominent veins. |
Fall colors are lemon yellow, scarlet, and bronze-red while some foliage remains gray-green. If this species of hardy geranium never produced a single bloom, I would still give it space in my garden.
Still going strong are numerous toadlilies (Tricyrtis) hybrids. Native Gentiana are quite lovely with blue flowers against the fall colors of red, yellow, and brown.
There is no shortage of color in my garden during October.