Nan Sterman thinks “we can understand our own gardens better by seeing what people do around the world.” To that end, she led a tour to venerable English estate gardens a few summers ago and was intrigued to discover that although the British did many things in their gardens that we might call “sustainable,” they never used that word. Instead, they talked about stewardship. “They are so far ahead of us,” she said.
Sterman, a garden writer and designer, discussed lessons learned from the garden tour at last month's San Francisco Flower and Garden Show. The gardens she visited were mostly extensive public gardens covering 100+ acres each, often centered on an historical estate.
At Wisley, the “flagship garden of the Royal Horticultural Society,” the staff of 90 use solar-powered machinery as much as possible. The perennial border, which has 16,000 plants, gets no fertilizer, water, or staking. In midsummer, the plants all get a “Chelsea chop” – cut by half – so that they will grow shorter and stockier for their second bloom. Then, at the end of the summer, the tall seedheads are “left in place for birds,” Sterman said, and finally cut down in February.
Construction waste offered an opportunity to create a new feature that had been popular in the 1700s: A big mound of soil at Wisley was made into a Fruit Mount. A path spirals to the top of the 12 ft. high hill, and the surface is “stabilized with wildflowers, which attract pollinators for the fruit trees at the top,” Sterman said. Apple trees are espaliered along the top railing, arranged in the order in which they were bred.
Pollinators and other beneficial critters are nurtured. At Hidcote, Sterman was impressed by an elaborate insect/wildlife hotel: an assemblage of pinecones, bricks, tubes, and tiles, meant to provide niches for bees, lacewings, and other beneficial insects, as well as lizards and birds. At one turn in the path, Sterman was stunned to see a 10 ft. by 10 ft. “tornado of bees” beyond a split-rail fence. Instead of trying to remove a bee swarm from this well-visited Arts & Crafts garden, the gardeners put up the fence and an educational sign. Other parts of the gardens featured plantings to attract pollinators.
Sterman also appreciated the extent to which pollinators were valued at Sissinghurst Castle. Near the entrance to the garden, she was about to collapse onto a bench until another visitor pointed to the sign on it: “There's a wasp nest nearby, so please don't sit here at the moment. Many thanks.”
Productive vegetable gardens and compost piles were proudly shown to visitors at several gardens. Sissinghurst's large no-dig organic kitchen garden supplies the on-site cafe, and part of its acreage is offered for allotments (analogous to community garden plots).
Climate change is acknowledged in gardens that have unwatered areas. “Even in England,” Sterman said, people realize that gardening will be changing but that people can still “create beautiful gardens post-pipes, that is, without irrigation.” The Dry Garden at the Cambridge Botanical Garden “uses all the traditional elements of the English garden but with different plants,” and noted British gardener Beth Chatto has been “experimenting with dry gardens for decades.”
This insect hotel, from the Ashby Community Garden in Berkeley, is smaller and less elaborate than the one at Hidcote, but it serves a similar purpose: offering shelter or nesting space for solitary bees and other beneficial insects.
The emphasis on stewardship in British public gardens extends to protecting and nurturing healthy populations of bees and other beneficial insects, even when visitors may be slightly inconvenienced.
Green lacewings (here, on a ceanothus in a California garden) are voracious predators of plant-eating insects. Like other beneficial insects, they benefit from a mindset of stewardship: no pesticides, some garden areas that are left to grow wildflowers or natives, and awareness of their role in a healthy garden.
© 2016 Tanya Kucak