Grow as perennials in Zones 14-24, H1, and H2, except as noted. Can also be grown as annuals anywhere or dug and stored. Outdoors, most grow best in pots in the ground or in hanging baskets in filtered shade, with rich, porous, fast-draining soil, consistent but light feeding, and enough water to keep soil moist but not soggy. Most thrive as indoor plants, in greenhouse, or under lath. Some prefer terrarium conditions. Almost all require at least moderate humidity. In areas with hot, dry summers or indoors in winter, set pots in pebble-lined saucers or trays kept filled with water to below pot level.
These (Superflorens) bushy, compact plants grow as perennials in listed zones, as annuals anywhere. Dwarf (6–8-in.) and taller (10–12-in.) strains grown in garden beds or containers, producing lots of small flowers in a white-through-red range. Plants bloom from spring through fall (use as a winter annual in hottest-summer climates). Foliage can be green, red, bronze, or variegated. In mild-winter climates, can live for years. Thrive in full sun in cool-summer regions. Prefer broken shade in hotter climates, but dark-foliaged kinds will take sun if well watered.