HARDY PERENNIAL PLANTS 211 



Propagation. It can be propagated either by seeding or divi- 

 sion. Seeding is more successful and a greater variety of flowers 

 are obtained in this way. More care and skill are necessary in divi- 

 sion on account of the fleshy root-stalk. 



PLUMBAGO (Valloradia) . CeratosHgina plumbaginoid.es, or 

 as it is more commonly called Plumbago Larpentce, is a hardy 

 species, with deep blue flowers, growing to a height of one foot. It 

 blooms from July till freezing weather. 



Culture. The plants should be lifted during the first half of 

 September, the shoots shortened back, and several pieces put to- 

 gether in 4-inch po.s, saving as many of the creeping underground 

 stems as possible. They require an intermediate temperature. 



Propagation. Propagation is effected by division. 



PRATIA. P. angulala is one of the most showy plants in cul- 

 tivation. It is sometimes called Lobelia littoralis. It is a slender 

 creeper, has white, star-like flowers, and is quick-growing. It is 

 admirably adapted to rockwork. It does well in shady places. 

 Where the Winters are severe, it should be lifted and wintered in a 

 cold house. 



Propagation. Quickly propagated by division; also by cut- 

 tings. 



PRIMULA (Primrose). There are few of the species but what 

 are worth growing. Many of them, however, are unsuited to the 

 chmate of the Eastern States, it being too cold in Winter and too 

 hot. in Summer. A few of the species and many of their varieties 

 do well. P- vulgaris and the varieties with double yellow, red, 

 purple, white, and lilac flowers succeed well if they are given water 

 during the growing period. They will even stand in almost full sun- 

 shine, but they thrive best in half-shaded spots. P. elatior is the 

 Oxlip, and what is known as the Cowslip is P. veris. Polyanthus 

 is a garden race, said to be a hybrid between the last-named species 

 and P. vulgaris. The different varieties are useful for rockwork and 

 for borders. A good selection of forms may be had from seed sown 

 in Spring ; but the plants will not bloom until the second year. Some 

 of the Himalayan species do fairly well in this latitude if given a 

 position shaded from sun in Winter and mulched in Summer. P. 

 denticulata and its forms are among the best. P. sikkimensis should 

 be tried in damp, shady ground by the margins of lakes. P. Sieboldii 

 produces pure white, crimson and lilac-colored flowers; very useful 

 for cutting. The plants have creeping root-stocks, and thrive best 



