The flowers are produced during July and August on spikes somewhat taller than the foliage. Continuous bloom from March to frost is possible with the right combination of materials. March to May flowering, needs minor spring-flowering bulbs. April to early June, uses perennials that flower and mature early. Late August to frost flowering may call for begonias.
Perennial begonias are also a possibility in warmer areas where they are hardy.
Robert Nuss is a horticulturist at Penn State. He coordinates all extension horticulture programs. He has bachelor's, master's, and doctoral degrees in ornamental horticulture and has been on the Penn State faculty since 1966.