Mossy Sandwort

Arenaria ‘Wallowa Mountains’ is a very low, compact evergreen groundcover with fine, bright green foliage that forms a cushion resembling moss. Plant Select and the Royal Horticultural Society list the same selection as ‘Wallowa Mountain’; its exact species and origin remain unresolved, so it is best described here by its established selection name. ## Garden Use and Character Use this cushion-forming plant in rock gardens, troughs, crevices, permanent containers, or between paving stones where its small scale can be appreciated. Plant Select describes it as exceptionally drought tolerant once established, with moderate-to-xeric water needs. Its fine green foliage provides the main ornamental effect; sparse flowers are a secondary detail, and reports differ on their season. ## Growing Conditions Plant in full sun or part shade and provide well-drained loam or sandy soil. Plant Select lists a mature height of about ½–1 inch and a width of 8–12 inches, with USDA hardiness in zones 4–8. Its story cautions that it may struggle in humid parts of zones 7–8. These compact dimensions suit small-scale rock and container plantings. ## Identity Plant Select’s profile and story, together with the RHS profile, support the same named selection, listed as Arenaria ‘Wallowa Mountains’ and Arenaria ‘Wallowa Mountain’. Plant Select’s account says the original species identification and collection history are uncertain. The selection is therefore recorded under Arenaria without assigning a species or asserting a native origin. [Plant Select profile](https://plantselect.org/plant/arenaria-wallowa-mountain/), [Plant Select story](https://plantselect.org/plantstories/field-of-green-arenaria-wallowa-mountains/), [RHS profile](https://www.rhs.org.uk/plants/348068/arenaria-wallowa-mountain/details). ## Maintenance Plant Select describes the selection as requiring little routine care. Allow the cushion to grow naturally; lightly brush away winter-damaged foliage if needed. Avoid persistently wet soil, especially in humid climates.