Redwood Sorrel
Oxalis oregana
Care
part shade
moderate
Medium; High organic content forest soil.
0–1ft tall , 6–6ft wide
Jan-Dec
Resistant
Friendly
Prized
Leaves eaten raw in salads or cooked; tart flavor; traditional use
Coastal redwood forests of northwestern California from Humboldt County south to Santa Cruz County, below 2000 ft elevation, in moist understory habitat.
Care Guide
Planting
Plant Redwood Sorrel in partial shade with rich, organic forest soil and medium drainage - it thrives in the moist, foggy conditions of coastal redwood forests. Space plants to allow room for spreading, as this groundcover will fill in any area with adequate moisture and shade. Plant in fall or winter when the Bay Area's natural rainfall supports establishment, avoiding the dry summer months.
After Planting
Water moderately through the first growing season to keep soil consistently moist; once established, you'll need to water only about once a month during summer, if at all. The plant is shallow-rooted and easy to control if it spreads beyond where you want it, so you can pull back sections as needed. Expect the foliage to fold up in direct sun - this is normal and a sign it prefers the shade you've given it. The biggest mistake is overwatering in summer; let the coastal fog and winter rains do most of the work once the plant is established.
Endangered & Threatened Species Supported
Northern spotted owl; federally and state threatened
Wildlife Supported
Birds
component of dense old-growth understory habitat structure
winter ground forager for insects and seeds in redwood understory
Insects
primary host plant for feeding and reproduction
overwinters in leaf litter and dense basal foliage
larval development on foliage and stems during growing season