623 Portulaca grandifloraCommon Names: moss rose, rose moss, sun plant, portulaca Family: Portulacaceae (purslane Family)
Moss rose is a prostrate, trailing, multi-branched annual with semisucculent stems and leaves. It reaches about 6 in (15 cm) tall with a spread of 12 in (30.5 cm). The reddish stems and the bright green leaves are thick and soft and juicy. The leaves are cylindrical, about an inch long, and pointed on the tips. The roselike flowers are about an inch across and come in bright colors like rose pink, red, yellow, white, and orange. Some are striped or spotted with contrasting colors. The flowers are borne on the stem tips, and they open only during bright sunlight, closing at night and on cloudy days.
There are several strains, cultivars and mixes available. Many have double flowers and some are up to 3 in (7.6 cm) across. 'Sundance' has double flowers to 2 in (5 cm) across. The Sundial series cultivars bloom in cooler and cloudier weather with double flowers in a wide variety of colors. 'Afternoon Delight' stays open longer in the afternoon.
Portulaca grandiflora is originally from the hot, dry plains of southern Brazil, Uruguay and northern Argentina, moss rose is cultivated throughout the world as a favorite garden annual. It has escaped cultivation in a few areas, including central Florida.
CultureMoss rose grows well in poor, sandy or gravelly soils. The soil must be very well-drained. It can be bothered by root-knot nematodes and aphids. Aphids can be washed off with a stream of water or sprayed with soapy water. There's not much you can do about root-knot nematodes except to grow plants that are resistant. Light: Needs full sun to flower. Moisture: Drought tolerant, but flowers best with regular watering. Don't water with overhead irrigation, which can damage the flowers. Hardiness: USDA Zones 5 - 11. Plant seeds or set out moss rose plants after all danger of frost has passed. Propagation: Sow seeds in place. They are as tiny as dust, so mix them with sand before sowing to make them easier to scatter. In warm climates, moss rose may self-seed.
Moss rose makes a beautiful ground cover in a dry or rocky area, although it cannot be walked on. Use moss rose as edging at the front of borders or in the cracks in a rock wall, or the spaces between stepping stones. It's perfect for a hot, dry, south facing slope. Plant moss rose in a container or hanging basket and let it spill over like a sedum.
Moss rose is a beautiful, bright colored, low growing annual that blooms all summer long with little or no care required. It is one of very few annual succulents.
The related purslane (P. oleracea) is a bothersome weed in warm climates, although it is widely cultivated for food and has been for more than 2000 years. In fact, purslane, which is used raw in salads and cooked like spinach as a potherb, is very high in vitamins A, B1 and C. It is available commercially in both ornamental and culinary cultivars.
Steve Christman 12/16/99; updated 6/25/03, 9/11/03