R. Fraley

Lupinus perennis

Clade: Angiosperms

Clade: Eudicots

Order: Fabales

Family: Fabaceae

Genus: Lupinus

Sundial Lupine (Lupinus perennis) is a native perennial wildflower in the pea family, recognized by its star-like palmate leaves and upright racemes of blue, violet, lavender, or sometimes pale whitish pea-like flowers.

Common names include Sundial Lupine, Wild Lupine, and Wild Blue Lupine.

For representative images and visual context, see the page Sundial Lupine in the Gallery section.

Description

Lupinus perennis is recognized by:

The leaves are one of the best field marks. Their spoke-like shape gives the plant the “sundial” impression suggested by the common name. The flowers show the typical pea-family structure, with a banner, wings, and keel arranged into a compact blue-violet bloom.


Soil and Habitat

Sundial Lupine is associated with open, sunny, well-drained habitats, especially sandy soils. It is often found in oak savannas, pine barrens, sandy prairies, open woods, roadsides, and restoration plantings where competition from taller vegetation is limited.

In Minnesota and the upper Midwest, it is especially connected with sandy oak and jack pine savanna habitats.


Similar Species

The most important lookalike is Bigleaf Lupine or Western Lupine (Lupinus polyphyllus), a larger western species that is often planted and may escape cultivation. It tends to have larger, more numerous leaflets and heavier flower spikes. Because common names such as “wild lupine” can be used loosely, the scientific name is important when identifying or planting lupines.

The plants photographed here appear consistent with Lupinus perennis: relatively slender flower spikes, blue-violet pea-like flowers, hairy stems, and palmate leaves with narrow leaflets.


Ecological Notes

Sundial Lupine is especially important because it is the larval host plant for the Karner blue butterfly. The plant’s need for sunny, sandy, open habitat connects it to fire-influenced landscapes such as oak savannas and pine barrens, where periodic disturbance helps keep woody growth from shading out the lupines.

As a member of Fabaceae, it also participates in nitrogen-fixing relationships with soil bacteria, allowing it to grow in relatively poor sandy soils.


Notes from the Photos

The gallery images show several useful identification features:

The clearest identification image is the foliage detail, where the palmate leaves are visible beside the flower stalk. The wider images are useful for showing the plant’s open, grassy habitat and the way multiple flower spikes repeat through the scene.