Nasturtiums come in three types: dwarf, semi-trailing, and single flower climbing. Dwarf types are bushy and compact and include the cultivars 'Alaska', 'Empress of India,' 'Strawberries and Cream,' and 'Whirlybird.' Semi-trailing types reach a length of two to three feet, making them ideal for hanging baskets. The Gleam series is a good choice here, having been named an All-America Selections winner in 1935.
The single flowering climbing types like 'Jewel of Africa' send out six to eight foot runners that climb trellises like vines. Colors of this type are bright and range from yellow and orange to rose and crimson. Vines are strong and have fragrant flowers.
Nasturtium is one of the easiest flowers to grow from seed. The best flowering will be in full sun, but they will tolerate partial shade. Seeds can be sown directly in the garden beginning in late May or started indoors to get a good head start on the season. However, as nasturtiums do not fare well when transplanted, use peat pots and plant these directly in the soil.
Nasturtiums are not choosy about their soil, but, given a choice, do prefer a light, sandy soil. Don't spoil them with rich, fertile soil and fertilizers as this will only result in lush foliage and few blooms.