Podophyllum Peltatum (_Duck's Foot, or May Apple_).--Grown chiefly for its foliage and berries, this hardy herbaceous perennial forms a pleasing spectacle when planted in moist soil under trees; it likewise makes a splendid pot-plant. A mixture of peat and chopped sphagnum is what it likes. The pots are usually plunged in wet sand or ashes on a northern border. It is propagated by cutting the roots into pieces several inches in length, with a good bud or crown on each. During May and June the plant produces small white Dog-rose-like flowers. Height, 1 ft. Poinsettia Pulcherrima.--A stove evergreen shrub which produces lovely crimson bracts in the winter. Plant in sandy loam, give plenty of water to the roots, and syringe the leaves frequently. In early spring cut down the branches to within three or four eyes of the old wood. These cuttings, if laid aside for a day to dry and then planted under glass, will form new plants. It flowers in April. Height, 2 ft. Polemonium (_Jacob's Ladder_).--Hardy perennial border plants of an ornamental character and of the easiest culture. Any soil suits them, and they merely require sowing in the open either in spring or autumn. P. Richardsoni is most commonly met with, its blue flowers being produced in early autumn. Height, 1-1/2 ft. Polyanthus.--Sow the seed late in autumn in well-drained boxes of light, rich mould; cover it very lightly, place under glass, and water sparingly, but give enough to keep the plants moist. The seed requires no artificial heat to germinate it. The roots should be divided each year as soon as they have flowered, and fresh soil given. The single varieties only are florists' flowers. The Polyanthus is a species of primrose, grows best in a rather shady position in a loam and peat compost, and produces its flowers in May. Height, 6 in. Polygala Chamaesbuxus.--A hardy evergreen trailing plant requiring a peat soil in which to grow. It may be increased from seed or by division of the roots. May is the time at which it blooms. Height, 6 in. Polygala Dalmaisiana.--This showy evergreen shrub needs a greenhouse treatment. Soil--three parts peat, one part turfy loam, and a little sand. It flowers in March. To increase it, top the shoots, which will cause it to throw out new ones. Take the new growth off when it is 3 in. long, and place it under glass in a propagating house. Height, 1 ft. The hardy annual varieties of Polygala are obtained by seed sown in peat. These flower at midsummer. (_See also_ "Solomon's Seal.") Polygonatum.--These pretty herbaceous plants are quite hardy. The flowers, which are borne in May or June, are mostly white. Plants succeed best in a rich soil. They may be raised from seed, or the roots can be divided. Height, 1ft. to 3 ft.