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 pentsterons .