Improving rocky, clay soil allows a garden to flourish. See how this New York couple worked with what they had to create a lush garden.

By C. L. Fornari
October 04, 2018

Somewhere in the world are gardeners blessed with the seemingly contradictory “moist but well-drained soil” that can grow almost anything. Landscapes full of naturally deep, organically rich loam that allows excess rainfall to percolate away may sound like a horticultural fantasyland. Let’s face it: Many gardeners have less-than-ideal soil. They wonder if it’s possible to create beautiful gardens when faced with difficult conditions such as bedrock and poorly drained clay.

The answer is yes, and Norma and Dennis Coney’s gardens are proof. The couple gardened in the sandy soil of Oswego County, New York, for many seasons before moving to their current property in Schoharie County, where the growing conditions are much more difficult. Now they plant in clay that’s layered over rock—but their gardens thrive.

Clay and rock provided just the first of many tests for Norma and Dennis. Their land in the Catskill Mountains is at an elevation of 1,880 feet, so spring arrives late and winter comes early. In addition to the challenges of short growing seasons, they found that there was, in the best of places, a 2- or 3-foot layer of clay over bedrock. Other areas yielded exposed bedrock or only a few inches of clay over stone.

For all who garden, the land has the final say on everything from plant selection to garden design. Gardeners need to be flexible. It’s crucial to be willing to work with what you’ve got, to gradually improve the soil when possible, and to learn over time which plants will grow in less-than-hospitable conditions.

For the Coneys, the basic layout of the gardens was determined by the existing landscape. “The gardens were designed to work around the areas where nothing would grow,” Norma says. “They followed the natural bedrock. Beds evolved organically over time, set into the contours of the land.”

Preparing the Garden

No matter what growing conditions a gardener starts with, a future garden needs to be cleared of unwanted plants and debris. For the Coneys, this meant pulling saplings. “There were at least 75 maple seedlings growing in about 5 inches of clay soil,” Norma says. “We had to pull those out before we could make a garden.”

The Coneys found that many herbs they’d grown in the past didn’t do as well in clay as they had in sandy soils. So Norma planted perennials among those herbs that did thrive. Using the exposed bedrock as an opportunity, Dennis became interested in hardy alpine plants and developed an alpine garden in the shallow soil of the rocky spaces.

The rock offered more than a chance to discover new plants and garden styles; it was also beautiful. “We have never relied on hardscapes other than the native rock,” Norma says. They regard exposed rocks and the stones that they’ve stacked into walls as visual assets, defining borders and adding contrast in texture and color.

Although the rock proved its value, the clay soil did not. The Coneys worked constantly to improve the existing soil. Whether soils are sandy or clay, methods to enrich them are the same. Organic matter such as compost or aged manure is the answer in both situations. “Compost went to the vegetable garden,” Norma says, “and we used manure in the flower garden. But over time our primary soil amendment has been leaves.”

The Coneys’ gardens have grown and developed in both design and diversity over time as the couple planted for beauty as well as for the support of pollinators. Good soil is underneath it all. “Having dealt with both sandy and clay soils over the years,” Norma says, “soil building is our salvation.”

Finding Plants that Worked

Daylilies with long, thin petals are often called spider forms. This one, Pink Super Spider (Hemerocallis ‘Pink Super Spider’), grows well in this Zone 5 garden. Norma and Dennis grow billowing beds of perennials in Upstate New York.

Planning for All Seasons

Although this garden is at its peak of colorful bloom in midsummer, the landscape is interesting for many months. “The garden is a three-season garden,” Norma says. “Spring is dominated by contrasting foliage, unfurling hosta and fern, allium, Pulmonaria, and Epimedium. Later in the summer and early fall there is Rudbeckia, sedum, phlox, aster, Boltonia, and Cimicifuga.”

Free Clay Soil Garden Plan

Planting in Clay Soil

In addition to daylilies, the Coneys found that other perennials, such as the creamy astilbe, could thrive in the clay and short season of their high elevation. In a garden where clay holds onto moisture and the temperatures don’t get too hot, astilbe can be successful in sun or part-shade. Other potential plants for a setting like this include lungwort, bee balm, and coneflower.

Making Amendments to Clay

Statuesque Asiatic lilies and other perennials thrive in beds mulched and improved with leaves. Norma and Dennis picked up hundreds of bags from neighboring towns where homeowners had put out bagged leaves for disposal. Pine needles, hulls, and seaweed can also be added to clay soil.

Using the Natural Landscape

The Coneys have designed around what nature provided by leaving the surface stone and adding stacked stone walls. They were careful to place plants according to which plants would be likely to thrive in the rock or neighboring clay. A colorful garden fountain brings the colors of the flowers forward in the garden bed.


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