Propagated by seeds, the hardy species sown out-doors and the tender ones under glass. Cuttings may be taken from firm shoots and inserted in a sandy position under glass. The ordinary flax is sown directly in the field.
Lippia, including Aloysia, Zapania. Verbenaceæ.
Seeds. Usually by cuttings of young shoots, which will root freely in sandy soil in a close, warm frame. If it is not possible to secure the necessary heat, cuttings of the hard wood can be used in autumn, under glass.
Liquidambar (Sweet Gum). Hammelideæ.
Seeds, which should be stratified or sown as soon as ripe. Many of the seeds may lie dormant until the second year.
Liquorice. See [Glycyrrhiza].
Liriodendron (Tulip-tree, White-wood). Magnoliaceæ.
Increased by stratified seeds. Named varieties are grafted on seedlings. The seeds of the tulip-tree are apt to be hollow, especially those grown along the eastern limits of the distribution of the species.
Lisianthus. Gentianeæ.