Lithodora diffusa 'Grace Ward' (Lithodora)

Lithodora diffusa 'Grace Ward' is one of the most intensely blue-flowering ground covers you can grow in a Pacific Northwest garden. The flowers are a true deep gentian blue, vivid enough to stop you in your tracks, and they appear in generous flushes from late spring into summer against a backdrop of small, deep green evergreen leaves. The plant stays low and mounding, typically six to eight inches tall and spreading to about eighteen inches wide, making it ideal for draping over the edge of a wall, carpeting a rock garden, or filling the front of a sunny border.

Lithodora has one firm soil preference: it requires acidic, well-drained conditions and will not tolerate alkaline or waterlogged ground. On the Oregon coast, a lean, acidic soil works perfectly. Plant it in full sun for the best flowering, though it appreciates some afternoon protection in warmer microclimates. Avoid heavy clay and skip lime applications near this plant.

'Grace Ward' is considered one of the best-performing selections for Pacific Northwest gardens.