Plant of the Month for August 2018

Polygala calcarea

Description and General Information:

Called the chalk milkwort, Polygala calcarea is a low growing, mat-forming plant 2 cm tall, with small, elliptical evergreen foliage. In late spring pants produce short spikes of deep blue flowers with a central brush of white anthers.  It is distributed on limestone substrate from southern England to northern Spain.


This species prefers alkaline soil and well-drained but gravelly soil that stays reasonably moist.  It is overall a slow grower but long-lived if grown under good conditions. 'Lillet' is the standard cultivar offered by nursuries and has been awarded a AGM by the RHS.

Blooming Season:

May and June.


Seeds, cuttings, division


Large plants may be dug and divided after flowering.


Direct sow at 20 C; overall slow and poor germination rates.


Cuttings is the preferred method for propagation.  Take cuttings just after blooming.

Plant Details Page