Blue Cardinal Flower

About this plant

Lobelia siphilitica, commonly known as Blue Cardinal Flower, is a stunning perennial celebrated for its intense, true-blue blossoms. Rising gracefully on sturdy stems, these captivating flowers create a dramatic vertical accent in the late summer and early fall garden, attracting a parade of pollinators. Thriving in consistently moist to wet conditions, this native beauty is an exceptional choice for rain gardens, pond margins, or boggy areas where other plants might struggle. Its upright growth habit and brilliant coloration make it a focal point in any landscape demanding a touch of natural splendor. Easy to grow and relatively low maintenance, the Blue Cardinal Flower offers an elegant solution for adding long-lasting color and ecological value to your garden, ensuring a spectacular display year after year.

Installation timing

When we're in season, outside of the winter months, our goal is to get your plants installed within about two weeks. That window gives us enough time to secure your plants from our supplier and find a spot on the schedule. Throughout the process we stay in touch through notifications and your existing client portal on the main A Cut Above website, which is separate from this landscaping plants shop.

Care & maintenance

Requires consistently moist to wet soil. Mulch to retain moisture, especially in drier climates. Can be divided every 2-3 years in spring to maintain vigor. Deadhead spent blooms for a tidier appearance, though this is not strictly necessary.

Watering suggestions

Proper watering is the single most important factor in your plant's survival after installation. Newly installed plants have a limited root system and rely on you for consistent moisture while they establish.

• First 2 weeks: Water deeply every day (or every other day in cooler, wet weather), soaking the root ball and surrounding soil.
• Weeks 3–12: Water deeply 2–3 times per week, adjusting for rain, heat, and soil drainage.
• After establishment: Water deeply about once a week during the growing season, and more often in extreme heat or drought.
• How to check: Stick a finger 2–3 inches into the soil near the roots — if it's dry, it's time to water. Deep, less-frequent watering encourages strong roots; shallow daily sprinkles do not.
• Avoid: Overwatering (soggy, waterlogged soil) is just as harmful as underwatering and can drown roots.

Watering needs vary by plant, season, soil, and exposure. Because proper watering is the customer's responsibility after installation, please make sure you understand and can follow these suggestions before ordering.

Good to know: plants and trees purchased from and installed by A Cut Above include a one-year limited warranty from the date of installation. Because plant survival depends heavily on proper watering and care after installation, losses caused by improper care, neglect, animal or chemical damage, or extreme weather are not covered, and we must be given the chance to inspect a struggling plant before it's removed or replaced. Coverage is one replacement per plant. Read our warranty info.