Psidium. See [Guava].
Psoralea. Leguminosæ.
Seeds, divisions and cuttings of growing shoots, placed under glass. The tubiferous species, as the pomme blanche or Indian potato (P. esculenta) are increased by tubers or divisions of them.
Ptelea (Hop-tree). Rutaceæ.
Increased by seeds, sown in autumn or stratified, or by layers. The varieties may be grafted on the common forms.
Pteris (Brake, Bracken). Filices.
Easily grown from spores. See [Ferns].
Pterocarya. Juglandeæ.
Increased by seeds, suckers and layers.