Plant of the month, Lobelias

Blue lobelia and cardinal flower are an easy plant to grow in the rain garden. Lobelias are a good starter plant for instant gratification the first year. The flower heads can be cut back after the bloom to keep a nice tidy look. Lobelias grow easily from seed and can fill in hard to reach muddy spots in the center of the garden. They look great growing among sedges or rushes. Their blue and red blooms are a perfect complement to the many yellows blooming in late summer.

Blue lobelia, Lobelia siphilitica, grows well in wet areas of the garden in full sun. It can tolerate part shade and medium garden soil. Most leaves are at the base but it will send up a 3 ft tall flower stalk. It blooms in various shades of blue July to September. Blue lobelia will tolerate deer, heavy shade, and wet soil. Provides late summer bloom to the perennial border, wild garden, native plant garden, woodland garden or naturalized planting. Also effective near ponds or streams.

Red Lobelia, also known as cardinal flower, Lobelia cardinalis, grows well in wet areas of the garden in full sun. It can tolerate part shade and medium garden soil. The flower spike can reach 4 ft tall, blooming scarlet red, white or rose in July to September. Cardinal flower adds late summer bloom and height to raingardens, wet meadows, along streams or ponds, and gardens as long as soils are kept uniformly moist. It will tolerate rabbit and deer.

Lobelias, especially cardinal flower can be short lived plants. They are easy to propagate from seeds, so plan to collect some seeds each year to grow more plants and keep your population thriving. Collect lobelia seeds as soon as the seed stalks dry. The seeds are a dark brown dust and are easily blown away and lost. I like to tip the seed stalk over into a white bucket and tap out the seeds. Dropping them into a white container helps to see how many have been collected. Lobelia seeds can be kept with some damp soil in the fridge over the winter to sow in trays in the spring. Or the seeds can be directly sown onto the garden by sprinkling the seeds over the soil. Because the plants grow in wet areas the seeds will move with the water so I plant them slightly uphill from where I want them to grow.

Lobelia flowers are very attractive to butterflies and hummingbirds. It looks great to plant the various colors of lobelia together creating a color variation ranging through white, pink, red, magenta, purple, blue, and light blue. The hues of color come from genetic variation and can pass on that particular shade to their offspring. Blue lobelias, especially, come in a wide range of shades of blue, purple, and white.