I have mentioned before that I volunteer with the Horticulture staff on the Rose Kennedy Greenway in Boston. This 1.5-mile long, 1-block wide garden was built after the Big Dig in Boston moved a highway underground. Today it is managed and maintained with an organic horticulture program and includes a sizeable percentage of native plants and cultivars in its mix.
Each week I join a small crew of volunteers and staff to work on a specific section of the Greenway, so we get to know the plants and conditions there quite well, and we get to observe the changes over the season. There is one particular corner where the design enchants me, and I want to share how it has emerged and blossomed out this spring.
This is the first planting bed you see when entering this section of the park, at the corner of Pearl Street and Purchase Street; a path continues into the park on the right. It’s a wide bed with an Japanese Tanyosho pine tree (Prunus densiflora), and a sweep of low-growing plants around its feet. This is a part-shade garden thanks to the pine, and has fertile soil with some supplemental watering.
In this picture, where new plants are just emerging in early April, you can see the burgundy coralbells (Heuchera sp.), light green foamflower (Tiarella sp.), and mid-green columbine (Aquilegia canadensis) just coming up. You can also see a handful of daffodils in the back.
Three weeks later, in early May, the ground is completely covered, the foamflower is in full bloom, and the columbine is just beginning to blossom. On the right edge is a stand of bishop’s hat (Epimedium sp.) and stonecrop (Sedum ‘Autumn Joy’), and in the rear you can see a large stand of variegated Solomon’s Seal (Polygonatum odoratun ‘Variegatum’) where there was bare ground in the last picture.
On June 1, the columbine is glorious in its bloom and the burgundy coralbells have put up some slender pink flowers. I just love how these plants have spread out and interweave to form their own plant community. The coralbells and sedum mostly stay where they were planted, but the tiarella spreads out gradually by rhizomes, the columbine self-seeds into any small open space, and the epimedium spreads by expanding clumps. Every year it’s a slightly different configuration.
Behind the Solomon’s Seal in the last photo above is a large stand of goatsbeard (Aruncus dioicus). It erupted in these feathery blooms the second week in June. These plants are especially robust and seem to love their conditions here on the Greenway. I grow some of these in the edge of the woodland garden on the Cape and they get to about two-thirds of this size.
Just this week (the third week in June) the end of the spring bloom season can be seen, but an interesting tapestry of foliage remains for the summer.
It’s fun to imagine replicating this with all native plants. Of the plants in this grouping, the coralbells, tiarella, columbine, and goatsbeard are all natives. The Solomon Seal could easily be replaced with a stand of native ferns, such as Lady fern. And I’d be OK with leaving smaller stands of the epimedium and sedum for more texture in the foliage layer.
The trickiest thing to replicate is the pine. It provides a major focal point with its interesting multiple trunks and foliage on the upper branches. I don’t know of any native conifers that would replicate this look, so I might consider a small multi-stemmed deciduous tree. Serviceberry (Amelanchier sp.), river birch (Betula nigra), and sweet bay magnolia (Magnolia virginiana) look like they would do the trick.
By the way, in the background across the pathway you can see a stunning low hedge, and it’s a native plant! It’s Virginia sweetspire (Itea virginica). Right now it is covered with a narrow white bloom at the end of the branches, and in the fall the foliage will turn bright red. While it’s not native to New England, the cultivar ‘Henry’s Garnet’ grows fine in my Cape Cod garden.