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Prairie alumroot is a popular choice for ground cover, though the green or white flowers can be an added interest in a prairie or rock garden in midspring to early summer. This is a durable, long-lasting perennial that is easy to grow in sunny to partially shady areas with well-draining soils. This species is native to the Chicago region according to Swink and Wilhelm’s Plants of the Chicago Region and current research.

  • Family (English) Saxifrage
  • Family (botanic) Saxifragaceae
  • Tree or plant type Perennial
  • Native locale Chicago area, Illinois, North America
  • Size range Medium plant (12-24 inches)
  • Light exposure Full sun (6 hrs direct light daily), Partial sun / shade (4-6 hrs light daily)
  • Hardiness zones Zone 3, Zone 4, Zone 5 (Northern Illinois), Zone 6 (City of Chicago), Zone 7, Zone 8, Zone 9
  • Soil preference Dry soil, Sandy soil, well-drained soil
  • Tolerances Dry sites
  • Season of interest early winter, midwinter, late winter, late spring, early summer
  • Flower color and fragrance Other
  • Shape or form Mounded
  • Growth rate Moderate
  • Wildlife Butterflies, Hummingbirds, Insect pollinators

Size and method of spreading:

If the tall flowering stems are present, this plant can reach mature heights of 2 to 4 feet tall, but without the flowers, the basal leaves often reach 1 to 2 feet in height. They are typically 1 to one-and-one-half feet wide. The primary method of spread for prairie alumroot is self-seeding.

Native geographic location and habitat: (include C-value if appropriate)

Prairie alumroot is native to the Midwestern United States. C Value: 10.

Attracts birds or pollinators: 

Hummingbirds and butterflies are common visitors of prairie alumroot. Prairie alumroot also attracts bees, including a specialist pollinator bee species (Colletes aestivalis). It is also a specialist host for a species of flea beetle (Altica heucherae) and some species of aphids. 

Leaf description:

The leaves of prairie alumroot grow around the base of the plant (basal leaves) and are attached by long, slender stalks (petioles) that are longer than the length of the leaves. The lower surfaces of the leaves and the petioles are hairy (pubescent). The upper surfaces of the leaves may be slightly pubescent or hairless (glabrous). In warmer climates, the foliage of prairie alumroot is evergreen, but the amount of evergreen foliage is temperature dependent in colder climates. The shape of the leaves is round with a slightly heart-shaped base (cordate), with five to nine shallow lobes in a handlike pattern.  The lobes have slight serration to the edges (serrate to dentate margins). The leaves are medium-green colored, but cultivars are available with variegation. 

Flower description:

Prairie alumroot flowers grow on individual stalks (pedicels) on groups of branching stalks that mature from the bottom upwards (panicles). These branching stalks originate on a long leafless center stem (scape) that rises above the foliage. The scape, branching stalks, and pedicels are covered in long, conspicuous hairs. Each flower has five petals that are often green or white in color, are surrounded by a five-lobed appendage (calyx), and have long string-like protrusions (stamens and style). The upper two lobes of the calyx can be slightly longer than the lower three, giving the flower an asymmetrical appearance. The stamens will be tipped with orange (anthers). The calyx, petals, and stamens are fused together at their base, forming a cup (hypanthium) around the female reproductive organs (pistils).

Fruit description:

The fruit of prairie alumroot are dry and will open to release the seeds when they mature (capsules). The capsules will have long, stringlike beaks. After the seeds open, they are carried by the wind.

Plant care:

Application of a winter mulch can help to prevent the roots of prairie alumroot from coming out of the ground due to the pressure created by freezing and thawing cycles. Prairie alumroot flowers are often removed when it is used as ground cover. Division is recommended every three to four years. 

List of pests, diseases, and tolerances:

No major pests or diseases are issues for prairie alumroot. Once established, prairie alumroot can be somewhat drought resistant.

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