Lobelia Plant Care: 3 Tips for Growing Lobelia Flowers

Lobelias are herbaceous flowering plants from the Campanulaceae (or bellflower) plant family. Their showy green leaves sprout vibrant flowers, generally ranging from dark blue to sky blue. On occasion, you might see rarer lilac, red, or white flower colors on some lobelia plants. Their overall bushy appearance is somewhat reminiscent of sweet alyssum. Gardeners sometimes treat perennial lobelia plants as if they’re annuals. This is due to how hard it is for them to survive many winter climates. Plan to reseed these plants unless you live in a temperate climate year-round.

Indigenous peoples were the first to cultivate these deer-resistant wildflowers, using lobelias as both foliage and herbal medicine. Scientists are still studying the effects of lobeline (an alkaloid from the plant) on asthmatic conditions and the brain’s dopamine and serotonin receptors.

Lobelias are bushy plants that come in a variety of shapes, sizes, and colors. Consider these four types of lobelia plants:

1. 1. Lobelia cardinalis: This type of lobelia plant stands out because of its vibrantly red flowers, as opposed to the usual blue ones. Rather than flaring out in the usual way, the tubular flowers of L. cardinalis remain more tightly knit than other lobelias.
2. 2. Lobelia erinus: If you plant this species outdoors, you should treat it as an annual lobelia. If you start the plant’s growth indoors or bring it inside before the first frost of the year, it can survive as a hanging basket perennial plant. Keep an eye out for the stunning ‘Crystal Palace’ and ‘Waterfall Blue’ cultivars.
3. 3. Lobelia inflata: If you consume this plant, alkaloids in it will act on the nervous system similar to how nicotine would. In some areas, people refer to the plant as Indian tobacco. Keep this plant in part shade, part sun to help it thrive.
4. 4. Lobelia siphilitica: Other common names for this plant include blue cardinal flower and great blue lobelia. L. siphilitica flowers will attract bumblebees, hummingbirds, and other pollinators to your garden.

Lobelia plants can be aesthetically pleasing and invite beneficial insects to your garden. Here are a few reasons why you might consider growing lobelias:

1. 1. Lobelias attract pollinators. Widespread lobelia shrubs and their flowers can form the basis for a butterfly garden. These insects, hummingbirds, and other pollinators will flock to these plants, which might prove to be a boon for the rest of your flowers, too.
2. 2. Lobelias can define your garden’s edges. If you’re on the lookout for an edging plant, a lobelia hedge could be an excellent choice. They provide ample opportunity for spacing and coalesce well around rock gardens, pathways, and the like. Edging lobelia requires a decent amount of pruning and upkeep to ensure your yard remains aesthetically pleasing.
3. 3. Lobelias can provide ground cover. Once you raise one lobelia plant, don’t be afraid to keep going with additional propagation—you’ll soon provide ample ground cover with the shrubbery and flowers. These easy-to-grow plants can light up your entire front or backyard with their vibrant foliage.

Offer the same care to lobelia plants you would to any other green element in your garden. Here are four tips to securing the ideal growing conditions for these plants:

1. 1. Adjust conditions for the climate. While lobelia will bloom beautifully in early summer, they’ll need some extra help to get from the first to last frost of winter. If you live in USDA Hardiness Zones 11–12, consider deadheading (cutting off dead flower tops to help them bloom more easily next year) the plants prior to the winter and leaving them outdoors. If you’d prefer not to deadhead or if you live in a colder climate, either be ready to reseed the following year or bring the plants indoors if possible.
2. 2. Provide lobelias with the right light. As their early to late summer bloom time approaches, make sure your lobelias have partial shade available to them. They can bear the brunt of full sun, but a bit of shade will help them grow to their best potential.
3. 3. Fertilize and water well. To help lobelia seeds with their germination, add some liquid fertilizer to moist soil every month or so as a supplement. Water well, but avoid waterlogging the rich soil to prevent root rot. Feed the ground with mulch and other organic matter to provide nutrients.

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