Here we are at the start of June. By the time summer arrives in three weeks, the majority of perennials in northern shade gardens will already have finished blooming. Is that surprising? You may never have realized it, but most shade tolerant perennials bloom in spring.
Think about it: hellebore, lungwort, violet, nodding mandarin, epimedium, Solomon’s seal, old-fashioned bleeding heart, most primroses, globeflower, Siberian bugloss, twinleaf, woodland phlox and many other shade standards are already done flowering. False Solomon’s seal, rodgersia, columbine, spotted geranium, bigroot geranium and mayapple are in bloom now, but they’ll be finished by late June, too. Foamflowers are fading (although if deadheaded they’ll put up more flower stalks), and the fruits of baneberry and goldenseal are already fattening up! Yup, flowers in the shade are mainly a spring thing.
What’s left to please the eyes of shade gardeners through the coming months? Goatsbeard, astilbe, hosta, bugbane, Japanese anemone, toad lily and woodland aster are all yet to come. There are more, of course, yet the fact remains that most shade perennials bloom very early in the year. I’d guesstimate 75% of them have wrapped up their flowering by the summer solstice.
There’s a good reason for that, of course. We tend to forget that plants don’t flower to please us. They have their own agenda: reproduction.
In our mostly deciduous temperate forest, the woodland is a full sun environment from November through April when the leaves aren’t on the trees. Most of that time, it’s too cold for perennials to grow, but in March and April, it’s just warm enough for them to shoot up quickly and do energy intensive things like flowering and setting seed while there’s plenty of sunlight to fuel the process. When the trees leaf out in May, many woodland perennials are winding down and looking forward to doing what we all would do if we could get away with it: lounging about all summer.
The tendency of woodland plants to flower in spring is the main reason why shade gardeners are often advised to stop focusing on flowers and instead rely heavily on exceptional foliage plants: ferns, hostas, sedges, and variegated plants such as (to name just one example) Brunnera macrophylla ‘Variegata’. Flowers will come and go in weeks, but foliage is season long.
Annuals can also help keep color going through the warm months, but the choices for shade in the north are severely limited. Begonias and impatiens are two obvious answers, and they’re readily available at low cost. Gardeners who have grown bored with wax-leaf begonias can try the dragon-wing types for some variety. These grow larger than wax-leaf begonias, are extremely floriferous and make more of an impact, but they also cost more since they aren’t available in 6-packs but have to be purchased in 4-inch pots.
Caladiums are another great choice for summer color in shade gardens, although once again the color is coming from leaves, not flowers. Caladiums are not cold hardy in the North and won’t survive winter in the ground, but they can be dug and stored, dormant, and regrown the following year if you have a bright, warm spot to start them indoors beginning in February or March. Be sure not to put them in the garden too early because they are very sensitive to cool nightime temperatures. Even here in southern New England, I’ve learned not to plant them outdoors until the first week of June. If you do get ahead of yourself with caladiums and they get whacked by an extra-cold night, they should spring back quickly as the weather warms even if their foliage dies back completely in the interim.
Don’t forget that lots of those spring blooming shade plants I mentioned earlier also have great foliage that will contribute to the beauty of your garden right up until the first frost. Rodgersia, epimedium, hellebore, Solomon’s seal and twinleaf are just a few examples of plants that would be worth growing even if they didn’t flower! So, when designing your shade garden, consider each plant’s total contribution to the effect through the whole growing season, not just the loveliness of its flowers, its most ephemeral aspect.
In a typical year, hellebores will be the first ornamental perennial to bloom in the Northeast. Although there are several species that can be grown in this region, especially in milder areas such as the coast and the lower Connecticut River Valley, one of the hardiest remains my favorite: Helleborus x hybridus (formerly and sometimes still known as Helleborus x orientalis).
Here in northwest Connecticut, hellebores send up their flower buds first, in March, before their leaves unfurl. As the month goes on, these succulent and tender looking shoots grow taller and taller, until they finally open up around April 1 to reveal clusters of 2″-wide, pendant blossoms. The species H. x hybridus is quite variable, with a range of subtle flower colors including creamy white, apple green, pale pink and burgundy. Its flowers often have striking speckled markings and prominent yellow anthers that are showy for about a week until the stamens fall off.
At first, hellebore flowers look a bit undressed because the plant’s leaves don’t come along until a few weeks later. When they do make their appearance, however, they are exceptionally attractive—leathery, glossy, palmate (arranged like fingers around the palm of a hand) and semi-evergreen.
Everything about hellebores is long lasting. Instead of dropping off after 2-3 weeks, hellebore flowers slowly fade to a pale green or buff color in much the same way hydrangea flowers do. They look good (although subdued) right up to the point when the seeds mature and are dispersed, usually in the latter half of June. Deadhead them before that point unless you want seedlings the following spring. In most gardens, the leaves will remain disease free and unblemished all season long, and will still be looking good when the first snow flies.
Shade tolerance: High
Hardiness: Zone 5; other species may differ
Size: Medium sized, with a height and spread of 15-18″
Native status: non-native to any part of North America
- Don’t cut back hellebore foliage in fall, even if you clean up the rest of your garden then. Why? Hellebores come up so early in the year, they are subject to damage from late frosts. These frosts won’t kill the plants, but they will kill the flower buds. As the plant’s shoots begin to emerge from the ground, last year’s leaves will provide some protection. After the new shoots have grown taller than last year’s leaves, you can groom them, cutting off the old foliage at ground level. Be careful not to accidentally cut off new growth—it’s easy to do. For a few more weeks after you groom them, it’s a good idea to keep some pine boughs or an equivalent handy to gently arrange over the new growth at night if a hard frost is in the forecast.
- Hellebores have to be several years old before they are mature enough to flower. A nursery plant in a 5-pint pot is probably only two years old, so don’t be surprised if it doesn’t flower its first (or even second) year in the ground. As long as the plant grows well and looks healthy, flowering should start when the plant is ready. A plant that fills a one-gallon pot should be old enough to flower its first spring after planting.
- H. x hybridus is often sold in a mix of undifferentiated colors. In other words, if the tag in the pot with your plant does not specify a flower color, but just says H. x hybridus, it could be any of the flower colors listed above. There’s no way to know which color you’ve got unless you buy the plant in bloom very early in the season and the plant is old enough to be blooming in the first place. In recent years, some growers have also offered hellebores in designated colors. I like the way the mixed colors look in the garden when hellebores are massed, but gardeners with color-theme gardens might prefer to purchase all of one kind.
- Hellebores have no special needs, but they don’t like excessive moisture. If put in exceedingly dank locations or planted in soils that drain poorly, rot of the crown may result.
- Hellebores self-sow moderately. Their seeds are large and heavy, so they don’t usually travel very far. If you don’t deadhead your plants before they drop their seeds, you’ll probably find a “skirt” of seedlings around their feet in spring. Move these to a nursery bed to mature or give them away to friends.
Bloom times and other life cycle stats are accurate for northwest Connecticut. In milder areas all aspects of a plant’s life cycle may occur earlier in the year, and in colder areas, later.