PENTSTEMON, in botany, a genus of plants (nat. order Scrophulariaceae), chiefly natives of North America, with showy open-tubular flowers. The pentstemon of the florist has, however, sprung from P. Hartwegii and P. Cobaea, and possibly some others. The plants endure English winters unharmed in favoured situations. They are freely multiplied by cuttings, selected from the young side shoots, planted early in September, and kept in a close cold frame till rooted. They winter safely in cold frames, protected by mats or litter during frost. They produce seed freely, new kinds being obtained by that means. When special varieties are not required true from cuttings, the simplest way to raise pentstemons is to sow seed in heat (65° F.) early in February, afterwards pricking the seedlings out and hardening them off, so as to be ready for the open air by the end of May. Plants formerly known under the name of Chelone (e.g. C. barbata, C. campanulata) are now classed with the pentstemons.