After Harvey Ladew read Rachel Carson’s 1962 book, “Silent Spring,” which many credit with jump-starting the nationwide environmental movement, he stopped spraying his 250-acre Pleasant Valley Farm in Monkton with DDT. Today, the folks who run Ladew Topiary Gardens use that decision as the guiding light for their commitment to an increasingly environmentally sustainable approach.
“Sustainable and green practice now seems the common way to do things,” says Emily Wehr Emerick, the gardens’ executive director. “It didn’t used to be. … Once everyone saw a problem and said ‘spray.’” Environmentally sound practices are key to maintaining the health of the 22 acres of historic gardens and five acres of meadows, says Emerick, as well as to reducing the roughly $400,000 annual cost of maintaining them.
Though environmental purists eschew lawns, Ladew would not be Ladew without the lush Great Bowl or the verdant lawns adjoining the two garden axes. But Tyler Diehl, head of gardens, has eliminated the mowing of some areas and adopted the ancient American Indian practice of burning the meadows every three to five years rather than mowing or spraying them.
Diehl and his crew add sand to the soil to prevent compacting in high-trafficked areas. And in several areas where thatch builds up and reoccurs, Diehl mows, scrapes it up, composts it, then re-seeds.
Perhaps most radically, instead of “blanket spraying” of broadleaf weeds, a small canister is used to target specific areas. Fifteen years ago, the turf was sprayed with fertilizers and weedkiller six times a year. Ten years ago, that was reduced to three times. Now only some areas receive treatment, and at most two times a year. Many areas receive no spraying at all.
The same is true in the Rose Garden. Diehl has reduced spraying to once a year and has gone back to planting old roses that require less maintenance. “Besides some ‘Knock Out’ roses we have only 18th- and 19th-century roses— no hybrid tea roses,” he says. “Ladew’s original climbing ‘New Dawn’ roses are well established. They’re also underplanted with banking plants, like perennial geraniums, to protect the beneficial insects that control aphids.”
Diehl and his gardeners have increased their tolerance of certain pests like aphids, and they don’t do anything to eradicate Japanese beetles on the roses. When he does spray the roses, Diehl uses the old-fashioned lime sulfur one year and dormant oil the next.
Throughout the gardens, especially on the 10-year-old Nature Walk, where tours and classes take place, Diehl is on a quest to curb the spread of non-native invasive plants. Trees like Norway maples, which Harvey Ladew planted, have now put out so many seedlings that they create a dense canopy that prevents understory trees and other plants from growing.
Other non-native invasives Ladew is working to reduce include multiflora roses, privet, garlic mustard, Canadian thistle, Japanese honeysuckle and miscanthus grass. “We can’t eradicate these completely, because the deer population feeds on them farther up the road, then deposits the seeds here,” says Diehl. But he tries. He pulls 75 percent of the plants. He also cuts them. Only if there is a big stand or something with a substantial trunk does he apply a pesticide to the stems by paintbrush or spray.
Diehl looks to natives first when he has to replace a plant. “Mr. Ladew used natives in his gardens— hemlocks, tulip poplars, sugar maples and locusts,” says Diehl. Because the aim is to preserve the original design and plantings, when a blue spruce dies another blue spruce is planted. But Diehl also uses natives like hornbeam and dogwood trees, witch hazel, clethra and Echinacea, and he’s replaced non-native invasive grasses like miscanthus with panicum (“switch”) grass.
For the past several years, Diehl and his team have devoted more time to sustainable practices like composting. The gardeners haul everything no thicker than a baby finger onto the compost piles, which are turned three or four times a year. “It takes a few years to pay off, but it pays off big,” says Diehl.
Although they do water the lawns (because they are key to the historic gardens) they do so judiciously. “Careful turf maintenance leads to healthier lawns, which in turn lead to a decreased need to water,” says Emerick. “The secret is to water thoroughly when you water. Turf is no exception.”
Undoubtedly Harvey Ladew would be proud of the increased knowledge of sustainable practices the current administration and horticulturalists adhere to in his gardens. Problems that plagued him, like the perennial challenges of hemlock pests and diseases, have been checked by more “green” protocol.
“Harvey Ladew was a hands-on gardener who knew his plants intimately,” says Emerick. “He knew a successful garden was a healthy garden. He’d be fascinated with what our horticulturalists know now, what we are learning, and, more importantly, what we are putting into practice every year.”