I really like small water gardens. As the gardener responsible for all of the exhibits and planting in the expansive water gardens that stretch through the Denver Botanical Garden’s 23 acres, I find my greatest challenge—and my greatest joy—in designing water gardens for small containers. Over the years I’ve learned that a teacup or half a cask of whiskey can house a water garden as exciting as anything I can dream up for the vast, watery canvas in the Botanical Gardens. In fact, small gardens can be even better; They allow you to get close enough to really appreciate the aquatic plants’ fascinating foliage, their spectacular flowers and their sometimes vivid scents.
They are also foolproof. If you end up with a design you don’t like, it’s easy to rearrange the plants. Small container water gardens are actually a collection of submerged potted plants, so rearranging a planting is as easy as rearranging the pots. And the plants are tough – most are almost difficult to kill and require virtually no care. All you need is a sunny spot with at least six hours of direct sun a day, something with water and a few plants. For me, water gardens in small containers have been an endless source of inspiration. And when you have mastered a small container, think about what you can do in a large water garden.
Anything that contains water can contain a water garden
The first step in designing a small water garden is deciding on the container. Anything that contains water is suitable. Even if not, there is still hope – holes can usually be sealed with cheap corks to make a container watertight.
I find widespread half barrels perfect. At 24 inches wide and 16 inches deep, they’re the ideal size to accommodate a dramatic display. The problem, however, is that toxins that leach out of the wood can pollute both water and plants. My solution is to buy a durable plastic liner that fits perfectly. These are available at many garden centers. Or you could line the barrel with a flexible PVC liner; Just be sure to use at least two coats if the material is 10 millimeters or less thick; Otherwise the liner will only last a year or two.
I’ve also used clay and plastic containers. To prevent water from seeping into and through the porous clay of a ceramic container, I apply two coats of sealer. I also like to use black plastic containers that look like cast iron pots. I’ve found that they come in three sizes – 15, 12, and 9 inches in diameter – and sometimes I want to display them all as a group.