This section is from the book "Commercial Gardening Vol2", by John Weathers (the Editor). Also available from Amazon: Commercial Gardening, A Practical & Scientific Treatise For Market Gardeners.
There are annual and perennial species in this genus, some being perfectly hardy, others somewhat tender. Of the perennial kinds S. latifolia is undoubtedly the best. It has large wavy leathery leaves, and produces immense, branching, flattish clusters of pale lilac-blue flowers in July and August, when they sell fairly well in market. There is a rare white-flowered form. This species may be increased by division in spring or by root cuttings inserted in sandy soil from October to January. Other useful perennial species are caspia, purple; Fortunei, yellow; Gmelini, deep lavender; Limonium, deep blue, with a white variety.
The annual Sea Lavenders have become popular of late years, chiefly for their cut-flower stems, which last a long time and are almost looked upon as "Everlastings" in the same way as the Helichrysums and Rhodanthes. They are best raised in gentle heat in the same way as China Asters in spring, and may be sold in boxes or pots for planting out in borders later on. The best kinds are Bonduelli, 1 ft., golden yellow; spicata, rose purple; Suworowi, bright rose; sinensis, pure white with canary yellow; superba, rose; sinuata, blue, with several showy varieties having rose and white flowers.
The more tender kinds of Statice are grown in greenhouses in a compost of loam, leaf soil, and well-rotted manure with a dash of coarse sand. They are raised from seed like the annual kinds, and are pricked out and potted on as they increase in size. No great trade is done in them, however. Perhaps the best kind is macrophylla, light blue with a rich dark-blue variety, atrocoerulea; and Bourgoei, purple and white; imbricata, pale blue; puberula, blue and white; rosea, rose; profusa, lilac.