Stylophorum (Celandine Poppy, or Poppywort).—­During May and June this hardy and handsome plant produces fine yellow flowers.  It accommodates itself to any soil, but prefers a rich, light one, and can be increased by seed sown in autumn or early spring.  Height, 1-1/2 ft.

Styrax.—­Ornamental shrubs requiring a light soil for their cultivation.  S. Japonica has Snowdrop-like flowers, and S. Obasa Lily-of-the-Valley-like scented flowers.  They are best propagated by layers.  Height, 4 ft. to 10 ft.

Sunflower.—­See “Helianthus.”

Swainsonia Galegifolia Alba.—­A graceful and charming cool greenhouse plant, with Fern-like evergreen foliage and pure white flowers, which are borne from April to November.  The soil most suitable for it is a mixture of loam and sandy peat.  Cuttings of the young growth planted in sand under glass strike readily.  Height, 2 ft.

Swallow Wort.—­See “Asclepias.”

Swamp Lilies.—­See “Zephyranthes.”

Swan River Daisy.—­See “Brachycome.”

Sweet Alyssum.—­See “Alyssum.”

Sweet Flag.—­See “Acorus.”

Sweet Peas.—­See “Peas, Sweet.”

Sweet Rocket.—­See “Rocket.”

Sweet Scabious.—­See “Scabious.”

Sweet Sultan.—­Sweet-scented, Thistle-shaped hardy annual flowers, which are very useful for cutting.  They may be raised in any garden soil from seed sown in March or April, and will flower in August.  Height, 1-1/2 ft.

Sweet William.—­Well-known hardy perennials, and deservedly favourite border plants, which may be grown in any good soil; but to have them to perfection they should be placed in light, loamy ground mixed with a little old manure and sand.  They can be raised with little trouble from seed sown thinly at any time between March and midsummer where they are to bloom, and may also be increased by dividing the old plants in spring.  They produce their flowers in July.  Height, 1-1/2 ft.

Symphoricarpus (Snowberry).—­A handsome species of St. Peter’s Wort.  The shrubs will grow in any ordinary soil, are hardy, and readily propagated by suckers, which are produced abundantly; or cuttings may be taken either in spring or autumn.  They bloom in August.  Height, 4 ft.

Symphytum Caucasicum.—­Hardy perennials.  They will grow in any soil or situation, even thriving under the shade of trees, and may be increased by division.  June is the month in which they flower.  Height, 3 ft.

Syringa (Lilac.)—­There are many choice varieties of these favourite shrubs, but any of them may be grown in a tolerably good soil.  They are propagated by layers or by suckers from the root.  They bloom in May or June.  Height varies from 4 ft. to 12 ft.

T

Tacsonia.—­A beautiful twining shrub belonging to the Passiflora family.  It should be provided with a rich soil, and, as the flowers are produced upon the lateral shoots, it requires frequent stopping.  Syringe frequently in warm weather to induce a quick growth.  It is a quick grower, and, when properly treated, a profuse bloomer, the flowers being produced in July, August, and September.  Cuttings of young shoots placed under glass in a sandy soil will strike.  Height, 20 ft.