Thermopsis

Thermopsis - Perennials, 2 to 6 feet high, slender in growth, and with long terminal spikes of attractive yellow Lupine-like flowers. T. montana is of graceful growth, and as it flowers at the same time it may be associated with the perennial Lupins and other border plants of the season. It grows best in good soil in an open border, and is a native of western N. America. T. rhombifolia is dwarfer and with rounded leaflets, growing well even in the driest places. T. fabacea comes very near T. montana, and has been confused with it, but it comes from the north of Asia; it is of fine habit and very free-blooming. A scarce but good kind is T. caroliniana, which grows 6 feet high in rich moist soil and blooms in July and August when all the rest have done. For the back of the border, or for massing in moist places, this is a truly handsome plant. T. barbata is a beautiful Himalayan species with purple flowers. Some of these plants spread freely at the root, and may be increased by division or seeds.