Otherwise known as Red Hot Pokers. Although the books generally suggest that they need dry stony and very well drained soils, our field grown varieties thrive in heavy loam soils with above average rainfall and suffered temperatures well below -10ÂșC with no additional protection. They must be much more tolerant than is commonly suggested. In cold areas one may need to be careful of long term freeze ups and where mulching the crown may be advisable. They last for ages in flower and offer vertical accents of colour in the late summer with very little trouble at all.