Saxifraga umbrosa
wood saxifrage
Overview
Saxifraga umbrosa is an evergreen, mat-forming perennial in the saxifrage family, spreading into low carpets of leafy rosettes 2-3 inches (5-8 cm) high. Each rosette is made of leathery, spoon-shaped dark green leaves 1-2 inches (2.5-5 cm) long, with rounded teeth along the margins and reddish undersides. In late spring and early summer, wiry reddish stems rise 10-12 inches (25-30 cm) carrying airy, branched sprays of small star-shaped flowers. Each flower is about 1/4 inch (6 mm) across, white to pale pink and finely spotted with red, giving the open sprays a misty pink effect. The rosettes spread by short runners to form dense, weed-suppressing mats. It is one parent of the garden plant London pride, S. x urbium. The mats stay green through winter. One limitation is that the foliage scorches in full sun and dry soil, so it holds its color in cool, shaded, consistently moist positions.
Native Range
Saxifraga umbrosa is native to the Pyrenees of northern Spain and southwestern France, where it grows in damp, shaded crevices, on rocky ledges, and along stream banks in mountain woodland.Suggested Uses
Used as evergreen groundcover and edging in shade, in rock gardens, and between paving in cool, damp spots. The leafy mats combine with ferns, hostas, and spring bulbs. It is grown to carpet shaded banks and the fronts of woodland borders.How to Identify
Appearance
Size & Dimensions
Height10" - 1'
Width/Spread1' - 1'6"
Reaches mature size in approximately 2 years
Bloom Information
Detailed Descriptions
Flower Description
White to pale pink with red spotsFoliage Description
Dark greenGrowing Conditions
Sun Requirements
Requires 1-4 hours of direct sunlight daily
• Full Sun: 6+ hours of direct sunlight
• Partial Shade: 3-6 hours of direct sunlight
• Full Shade: Less than 3 hours of direct sunlight
Care & Maintenance
Care Guide
Grow Saxifraga umbrosa in partial to full shade in cool, moisture-retentive but well-drained, humus-rich soil. The foliage scorches in full sun and dry conditions, so a shaded, evenly moist position keeps the mats green. Water in dry spells, and apply a thin mulch of leaf mold to conserve moisture. A slightly acidic to neutral pH of 5.5 to 7.0 suits it, and little feeding is needed. Pull or trim away dead rosettes and faded flower stems to keep the mat dense. Divide the runners in spring or autumn to fill gaps or start new patches.Pruning
Cut spent flower stems back to the foliage after bloom. Remove dead or scorched rosettes from the mat as needed. Lift and replant rooted runners in spring or autumn to renew thin patches.Pruning Schedule
J
F
M
A
M
J
J
A
S
O
N
D
summer
Container Growing
✓ Suitable for container growing
Minimum container size: 1 gallons