Plant of the Month August 2019: Downy Lobelia

A Painted Lady butterfly pollinates the blossom of a Downy Lobelia. Photo by Betsy Washington.

Several of our native Lobelias are well loved and absolutely beautiful. Cardinal Flower with its brilliant red flower spikes, and Great Blue Lobelia with its crowded spires of deep blue flowers, are familiar to many gardeners. Downy Lobelia (Lobelia puberula), which is less well-known, graces roadside ditches, low and upland woods, riverbanks and other boggy or damp areas. In fact, Downy Lobelia is the most common blue Lobelia on the coastal plain and throughout the Southeast U.S. All three of these Lobelias are wonderful garden additions that attract numerous pollinators to their tubular flowers, including many showy butterflies and hummingbirds. 

As you might expect, the stems and leaves of Downy Lobelia are covered in soft, short downy hairs. Its spires of soft lavender to blue flowers atop 3 – 5’ tall stems are less crowded than those of its Great Blue “cousin,” giving Downy Lobelia the elegant, “refined” look of some lavender bellflowers so admired in English gardens. Each flower has two flaring lips, of which the upper has two lobes and the lower lip has three, with a single white spot at its base. Downy Lobelia blooms from late July into November, but typically peaks in late August to early October. 

 An overlooked garden plant that is much tougher than it looks, Downy Lobelia prefers consistently moist soils but tolerates those that are occasionally wet and even dry soils. It is easy to grow in sun or part shade, and is at home in a soils ranging from our frequently sandy, to loam and clay. Like other Lobelias, Downy Lobelia is often considered a short-lived perennial, but produces lots of tiny seeds that will keep the population “blossoming” if the ground is not mulched heavily. Gently raking around the base of the plant each fall will encourage new seedlings. Downy Lobelia is even deer resistant. Often it is found in the wild growing with Joe-pye-weeds, Mistflower, and Goldenrods. Planting them together will create a stunning late summer-fall vignette. For even more stunning colors, add Cardinal Flower and Great Blue Lobelia.

Downy Lobelia is hard to find in regular nurseries, but all of these beautiful Lobelias and so much more will be available at the Fall Plant Sale of the Northern Neck Chapter of the Virginia Native Plant Society on September 7, at Wicomico Parish Church in Wicomico Church from 9 – 12. 

 Submitted by Betsy Washington, Northern Neck Chapter, Virginia Native Plant Societyi