About this time last year, the Puget Sound area experienced a “heat dome event” when temperatures rose to record highs and remained there for several days. While summer is perhaps the most obvious marker of our changing climate, its meteorological twin, drought, presents challenges to the garden even when temperatures are moderate.
It’s time to rethink landscape goals and planting strategies that are quickly becoming our new normal.
Jill and Howard Stein are committed to creating beautiful gardens that conserve soil and water resources. for 30 years, Stan DesignHis landscape design and consulting firm, has trended Waterwise Gardens at Bellevue Botanical Garden (12001 in Main St. Bellevue) from the design to its present maturity. Sponsored by Bellevue Utilities, Waterwise Gardens is a living laboratory and public display landscape filled with planting ideas and garden practices that are inspiring and informative.
The WaterWise Garden was designed to offer a range of growing conditions from the point of view of water conservation and efficiency. Flowering perennials in planting beds in full sun resemble flowers, such as stick flowers (diorama pulcherium), many hardy geraniums, Jerusalem sage (phlomis fruticosa) and Beeblossom (Gaura Lindheimerik) plants bloom throughout the dry season with little additional summer water, contradicting the idea that the water-friendly garden is weak on flowers. “We are dispelling the myth that [a drought-tolerant garden] All are lava rock and juniper,” remarks Jill. “It could be a really green garden.”
Nearby, a kitchen garden uses an efficient drip irrigation system to produce bountiful crops of vegetables, herbs, and fruits, and it benefits from regular applications of compost and mulch. These are the perfect conditions for tucking in what Jill calls “juicy annuals,” seasonal plants that need supplemental watering during the dry months. “It’s all about zoning your garden and grouping plants using water,” she observes.
Under mature pine and deciduous trees, hardy shrubs such as purple barberry (berberis thunbergii), Golden Mexican Orange (choice ternata) and oakleaf hydrangea (hydrangea quercifolia) thrives despite root competition, producing a matrix of colorful foliage and seasonal blooms. Mixed with woodland plantings, hardy fuchsia is a shade-loving, surprisingly satisfying shrub that blooms all summer. Textured ferns and grasses carpet the ground when combined with resilient groundcovers.
In addition to selecting suitable plants, Howard, the expert soil and water man at the design duo, recommends proper soil preparation, a generous layer of mulch, and caution when it comes to watering.
Stan Design has produced a number of online resources to guide the gardener through every step of the process. Visit Bellevue Botanical Garden WaterWise Garden Website To access the Natural Park Resources Library.
Discussing the lasting effects of our recent inclement weather, Howard advises, “Established plants that never need much in the form of supplemental water can be used this summer to make up for the damage done in the previous year. Some times deeper watering may be required.”
Even if you rely on an irrigation system, it’s a good idea to dig a few test holes in different parts of your garden to evaluate soil moisture. Light or infrequent irrigation can spread the top few inches, yet leave the deep root zone dry.
In keeping with the tall view, Stan is a fan of autumn plantings to take advantage of seasonal (and free) rainfall. What else to plant, think trees. Trees not only give structure and dynamic seasonal interest to the landscape, but over time they will provide precious shade. “Be strategic,” Howard advises. “Partial shade influences climate, provides little frost protection and cuts down on water use.”
If you’re up for some respite from hot, dry conditions, Waterwise Gardens is worth a visit in person.