Saxifraga aizoides
yellow saxifrage
Arctic and alpine Europe, northern Asia, and northern North America
Overview
Saxifraga aizoides, yellow or yellow mountain saxifrage, is a low, evergreen, mat-forming perennial in the family Saxifragaceae reaching 2-8 inches (5-20 cm) tall. It forms loose cushions and trailing leafy shoots of narrow, fleshy, oblong leaves 0.2-0.7 inch (5-18 mm) long, the margins fringed with a few short bristles. From June to September branched stems carry star-shaped flowers 0.3-0.5 inch (8-12 mm) across with five spreading petals in yellow, often spotted or flushed with orange to red, surrounding prominent orange anthers. It grows on wet, base-rich rock, gravel, and flushes beside mountain streams, in seepage zones, and on stony arctic-alpine ground that stays cool and moist. The fleshy evergreen foliage persists through winter beneath snow. One limitation is its need for constantly moist, cool, calcareous conditions, so it struggles in hot, dry, or acidic lowland gardens. It spreads slowly by creeping rooting shoots to form open patches over rock and gravel.
Native Range
Saxifraga aizoides has a circumboreal arctic-alpine distribution, occurring in the mountains of Europe, including the Alps, Pyrenees, and Scottish Highlands, across northern Asia, and in northern North America from Alaska and Canada south to the northern United States. It grows beside cold streams and on wet calcareous rocks and gravels.Suggested Uses
Grown in rock gardens, scree beds, alpine troughs, and the moist margins of streams and ponds, spaced about 6-10 inches (15-25 cm) apart. It binds wet gravel and stony banks and extends summer colour in cool alpine plantings.How to Identify
Appearance
Size & Dimensions
Height2" - 8"
Width/Spread6" - 1'
Reaches mature size in approximately 3 years
Bloom Information
Flowering runs from June to September, longest in cool, wet montane sites. The yellow petals, flecked with orange to red, open in small branched clusters and draw flies and small bees. Each flower develops into a reddish, two-beaked capsule that splits to release tiny seed.
Detailed Descriptions
Flower Description
yellow spotted orange to redFoliage Description
greenGrowing Conditions
Sun Requirements
Requires 4-10 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
Saxifraga aizoides grows in full sun to part shade on permanently moist, sharply drained, lime-rich gravel or rock. It needs cool roots and steady moisture, settling well beside water features, in scree beds, and in alpine troughs kept damp. Hot, dry, or acidic conditions cause it to scorch and die back. It is very cold-hardy, suited to roughly USDA zones 2 to 6, and keeps its leaves through winter. Propagation is by division of rooted shoots or by seed sown in autumn. It needs no feeding and has few pests beyond occasional aphids.Pruning
No routine pruning is required. Dead or frost-damaged shoots can be trimmed away in spring, and overgrown mats lifted and divided to keep them compact. Rooted pieces re-establish readily on moist gravel.Container Growing
✓ Suitable for container growing
Minimum container size: 1 gallons