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Lobelia
Lobelia erinus
Lobelia blooms from May through September.
Mature size, hardiness zones, sun and the trait tags were checked against named botanical sources for this plant. The bloom months and water need on this page were not.
Growing Lobelia
Plant it in part sun. It prefers moderate water. Expect it to reach about 8 in tall and 10 in wide at maturity, in roughly 1 year.
When to plant Lobelia
Wait until all danger of frost has passed, then plant out Lobelia into warm soil; in most zones that means late spring. Planted then, it flowers from May to September.
Month-by-month timing for your zone is on the planting calendar.
Comes in 5 varieties across 4 colors
Same plant, same care - pick the color you are growing.
Good to know about Lobelia
Curated from university extensions, botanic gardens and other primary sources, with the source named on every note.
Safety
Toxic to dogs, cats and horses, and to people if eaten in quantity. All parts hold lobeline, a nicotine-like alkaloid; keep pets and children from grazing it. per ASPCA and NC State
Worth knowing
It is a cool-season annual that stalls in hot, humid summer; when it flags, shear it back, feed and water, and it pushes a fresh flush and fall rebound. per NC State and Missouri Botanical Garden
Bloom all summer, or stall?
It depends on your summers: sources report continuous bloom where summers stay cool, but a midsummer stall and fall pickup where summers are hot and humid. per Illinois and NC State
Not the native lobelias
This blue bedding annual is a South African species, not the native perennials it is confused with: cardinal flower and great blue lobelia are separate North American plants. per NC State
Frost-tender annual
Treat it as an annual: it is frost-tender and dies at the first hard frost, so most gardeners replant it fresh each year. per NC State
Deer resistant
Reported deer resistant by NC State and Missouri Botanical Garden. As with all deer claims, that means seldom browsed, not truly deer-proof. per NC State and Missouri Botanical Garden
Draws butterflies
Its flowers draw butterflies and general pollinators, though the native perennial lobelias, not this annual, are the genus's real pollinator magnets. per NC State and Missouri Botanical Garden
What pairs well with Lobelia
Good companions share its growing conditions and add something it lacks: an earlier or later bloom, a lower carpet in front, or structure through winter.
Perennial Sunflower
Takes full sun to part sun and moderate water; overlaps, then carries the display into mid fall; stands well above at 4.9 ft, a canopy to plant beneath; both are strong pollinator plants.
Sneezeweed
Takes full sun to part sun and moderate water; taller at 3.3 ft, for the layer behind it; both are strong pollinator plants; its seed heads stand through winter, for structure and the birds.
Globe Thistle
Takes full sun to part sun and low to moderate water; taller at 3.3 ft, for the layer behind it; both are strong pollinator plants; its seed heads stand through winter, for structure and the birds.
Rosemary
Takes full sun to part sun and low to moderate water; opens in early spring and overlaps into this one's season; taller at 3.3 ft, for the layer behind it; both are strong pollinator plants.
Witch Hazel
Shares part sun and moderate water; blooms in late winter, before this one opens; stands well above at 9.8 ft, a canopy to plant beneath; both offer pollinator forage, in different months.
Azalea
Takes part sun to part shade and moderate water; opens in mid spring and overlaps into this one's season; taller at 3.9 ft, for the layer behind it; evergreen, so the bed keeps its shape through winter.
Lilac
Takes full sun to part sun and moderate water; opens in mid spring and overlaps into this one's season; stands well above at 9.8 ft, a canopy to plant beneath; both offer pollinator forage.
Asiatic Lily
Takes full sun to part sun and moderate water; taller at 3.3 ft, for the layer behind it; both offer pollinator forage; pink against blue, for contrast.
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