Tweedia Caerulea (also known as Amblyopetalum or Oxypetalum Caeruleum).
This is an untidy, rambling, scrambling little sub-shrub from Uruguay that is well worth persevering with because it is blessed with the most amazing flowers. Sky blue, sometimes tending towards turquoise, the flowers are borne in summer and autumn, in flattish heads comprised of 4 to 5 star-shaped, individual blooms.
It has pale green foliage with a downy feel and hairy stems that exude milky sap when cut. The plant should be pruned back in early spring to try and maintain an element of neatness. It enjoys rich, loamy soils, full sun and water during dry periods and is perfect for borders, rock gardens and even pots or containers. Tweedia Caerulea is tender to frost.