Last week I was on the Diller-von Furstenberg sundeck of The High Line, looking out at the Hudson River. From the sundeck you’ll find the closest and least obstructed views of the waterfront. The design of The High Line is broken up into different ecosystems, including a thicket, woodland, grassland, and a wetland area. The sundeck features plants found in marsh and wetland ecosystems. As you relax on the chaise lounges situated around the sundeck, it’s as if you are sitting amongst flora on the river’s edge.
I was leading an avid group of gardeners from my August Membership tour during this particular visit to The High Line, and we were admiring the rose mallows, of which the site has two different species. One is the swamp rose mallow (Hibiscus moscheutos ssp. palustris). This flower is commonly found growing on riverbanks, in freshwater and brackish marshes, swamps, floodplains, and wet meadows. It’s an adaptable native that doesn’t mind getting its feet wet, while it’s also tolerant of brackish water and deer resistant to boot. Swamp rose mallow has lovely pink flowers and makes a nice, full display on The High Line, tucked in with cattails (Typha laxmannii and Typha minima). It reaches 4-6 feet tall, flowers from July through September, and is hardy from Zones 4 to 9.
Every year, I travel to Cape Cod for a family vacation. I find it heartening to return to the same location, as there’s a comfortable familiarity that cannot be replaced. I know the bike paths, the homemade ice cream store, the quiet beaches, and the customs of the changing tides. We spend a portion of our days riding on the Cape Cod Rail Trail—a bike path that spans from Wellfleet just past the old Marconi telegraphy station down to Dennis. As we ride along the spectacular Cape Cod National Seashore, I admire the local flora, which there seems to be mostly native and exactly where it should be.
I soak in the sights, admiring my beloved beach plum (Prunus maritima) and the much adored bearberry (Arctostaphylos uva-ursi) that grows with such elegance and enthusiasm in its native habitat. As I make my way down the rail trail, one botanical encounter that I have every year in early to mid August is summersweet. I know I’m getting close when I smell that sweet fragrance wafting through the air. It grows in abundance on the side of wet marshes and persists on the edges of shaded woodland paths.
In Greek mythology, the goddess Persephone suspected her husband Hades, god of the underworld, of having a tryst with a nymph named Minthe. In a jealous rage, she transformed the lovely nymph into a perennial herb. Hades, unable to counteract his wife’s spell, bestowed Minthe with a sweet smell so that she would continue to delight those who came in contact with her.
Clearly, the aromatic qualities of mint are legendary. Through the centuries, mint has played an important role in many cultures, from the Greeks who rubbed mint leaves on their tables to welcome guests, to India, where it was strewn around temples and homes to clean the air. In the middle east, mint tea is often brought out to greet friends in the home.
Unlike many herbs that prefer sunny, dry spots, mints prefer moist soil in part shade/sun. As many of us know too well from experience, however, they are highly adaptable plants—and that’s putting it mildly. They grow in a wide range of conditions and are only too happy to expand their territory once they are planted in the ground. When I was a kid, my mother planted peppermint behind the vegetable garden; years later, the vegetable garden is gone, but the mint still thrives.
As we read in my post last week, it has been a difficult year for bigleaf hydrangeas (the mophead and lacecap hydrangeas) due to the late frosts in the spring which killed off many of the flowering buds. While weather is often the culprit for the demise of good flowering in hydrangeas, sometimes other factors come into play.
The lessons from this past year are clear: hydrangeas that flower on second-year wood (i.e., where the flower buds form in the previous season) are best sited in protected areas that are not exposed to harsh winter elements, such as strong winds and extreme temperature fluctuations.
Other factors can contribute to a lack of flowers. Too much shade will also hamper flower production, as will fertilizing too often with high nitrogen fertilizers—this will simply produce leafy growth with few flowers. Over- and under-watering your hydrangeas can also weaken the plant and prevent maximum flowering.
Earlier this season, Todd Forrest posted a blog entitled “Waiting for Hydrangeas”. He spoke of the cold spring we had where temperatures plummeted below freezing, destroying many hydrangea flower buds that were waiting to bloom this season.
While panicle hydrangeas (Hydrangea paniculata) and smooth hydrangeas (Hydrangea arborescens) flower on new wood, the bigleaf, mophead, and lacecap hydrangeas (Hydrangea macrophylla) that we all adore, flower primarily on old wood with the flower buds forming the previous season.
The re-blooming or remontant type that flower on both old and new wood have, as predicted, fared very well. We have a large planting of Endless Summer® at the train station entrance of the Garden at the Moshulu Gate. It has been flowering beautifully for the past month with new flowers starting to form as older ones fade. The first year these hydrangeas were planted the flowering was sparse, but now that they have established a solid root system and settled in they are floriferous.
Some vegetables seem to have more cachet than others. Sometimes it’s due to their flavor, other times to their versatility of use. And sometimes, they simply look too cool to ignore…or perhaps I should say “kool.”
The curious thing about kohlrabi is that the majority of people have no idea what it is. Few even realize it exists. In terms of its popularity, it’s the runt of the cabbage family—until you lay eyes on it, of course. At that moment, it’s probably the coolest cole you’ve ever seen.
Kohlrabi is a member of the cabbage or Brassica family. Its Latin name—Brassica caulorapa—means “stem turnip.” This is not an auspicious start for an up-and-coming member of the cabbage family. It starts its life looking like all the other members of the Brassica family—cabbage, broccoli, cauliflower—but then it comes into its own as it begins to mature.
Red feather clover (Trifolium rubens) Photo by Franz Xaver
Over the years, I’ve often given tours of the High Line to NYBG Members as part of our Membership tour programs. In fact, I’ve already given several this year and have more planned for August and October. And as I lead the groups through this unique space, we discuss architecture, ecology, design, and garden-worthy plants. Perennials in particular are always a hot topic.
I often warn the participants against some of the more rambunctious perennials, as they tend to have a thuggish habit. Instead, I recommend many of the other outstanding selections that you can find in the planting scheme created by Piet Oudolf, the High Line’s designer. The perennials planted there are chosen for their durability. Growing in 18 inches of porous soil atop abandoned railroad tracks that stand 30 feet above the ground, these plants are regularly exposed to intense urban heat, sunlight, and heavy winds—they have to be tough.
Piet Oudolf’s naturalistic planting style fits in superbly with the unstructured urban environment. He designed the High Line with plant communities in mind, using primarily native, resilient, and ‘low-maintenance’ plants that provide great diversity, seasonal change, and height and color variation.
The word “thyme” is derived from two possible Greek sources. One term means “to fumigate”—in ancient Greece, thyme was burnt at temples as incense, owing to its nice balsam odor. The other possible source is an association with courage. This association lasted from ancient Greece through the Middle Ages, when women gave knights gifts embroidered or decorated with thyme to inspire bravery.
These days, thyme—with its aromatic oils–is usually associated with invigoration. It is an asset in any landscape and makes a wonderful woody ground cover or a lawn alternative, as it is now commonly known. The diminutive pale pink or lavender flowers are a magnet for bees and help them to produce a wonderful honey. A large industry exists for extracting the herb’s essential oils. These oils are primarily distilled in the South of France, where the arid climate suits the plant’s Mediterranean temperament perfectly.
Some varieties of thyme have their place in the kitchen while others are more suited for the landscape. The most popular thyme is English thyme (Thymus vulgaris). English thyme is not native to England—the Romans introduced the herb—but the Brits took it on as their own. It has the strong, distinctive flavor that we most associate with the herb today.
Influenced by our culinary experiences, many of us likely think of basil (Ocimum basilicum) as originating in Italy. However, you might be surprised to find that this popular culinary herb is actually endemic to India, where it then spread to Asia, Africa, and Europe.
Basil is simple to sow from seed, and a cheap and easy way to include delicious diversity into your garden. We often combine several different types of basil together for an attractive display in the herb garden, vegetable garden, and sometimes a mixed border. But because basil is sensitive to frost, it is important to wait until the weather has warmed before it’s placed outdoors.
Much of the charm of the Conservatory’s Abby Aldrich Rockefeller Garden display comes from a glorious assortment of upright annuals. These make tall, statuesque, and often bold additions to any seasonal border. But while we often associate height in both perennial and annual borders with spires that guide your eyes upward—and there are certainly plenty of spires in this Groundbreakers display—what delighted me was the variety of other forms that gave height to the border.
One striking example was the monster-sized umbels of false Queen Anne’s lace, Ammi visnaga ‘Green Mist’. This opulent annual sports large Queen Anne’s lace flowers above ferny foliage. It grows to four feet tall and will create an impressive show whether placed in the middle or back of an annual border. It attracts beneficial insects into your garden and also makes a spectacular cut flower.
