Portulaca grandiflora

moss-rose

 

Portulaca grandiflora 'Sun Jewel'

Hook. 1829

pronounced: por-tew-LAK-uh grand-ih-FLOR-uh

(Portulacaceae — the portulaca family)

 

common name: moss-rose

Portulaca is the name the Romans gave to the purslane, derived from portare, to carry, and lac, milk, referring to the milky sap; grandiflora is from the Latin grandis, large, and flos, a flower.

This is a native of Argentine, southern Brazil and Uruguay. It is a favourite garden annual throughout most of the world, and has also escaped from cultivation and become widely spread in the Balkans, in parts of south Asia, and in central Florida, where it is close to becoming yet another invasive weed.

Portulaca grandiflora is a small prostrate, trailing, multi-branched annual with semi-succulent stems and leaves. It reaches about 15 cm tall with a spread of about 30 cm. The reddish stems and the bright green leaves are thick and soft and juicy. The leaves are up to about 2.5 cm long, pointed on the tips, arranged alternately or in small clusters. They act as a bright green succulent background for the blooms.

The rose-like flowers are 2.5 – 3 cm in diameter, with 5 petals, and the colour varying, depending on the cultivar – red, orange, pink, white, and yellow. The flowers are borne on the stem tips, and they open only during bright sunlight, closing at night and on cloudy days. Some cultivars produce double flowers, or flowers that are striped or spotted with contrasting colours; and some have much larger flowers than the cultivars usually grown. These flowers can be as much as 7 or 8 cm in diameter.

Some well-known cultivars are ‘Sundance’, with double flowers up to 5 cm across. The ‘Sundial’ series of cultivars bloom in cooler and cloudier weather, with double flowers in a wide variety of colours. ‘Afternoon Delight’ stays open longer in the afternoon.

Moss-rose is grown not only as a bedding plant, but also in containers, often with other plants sharing the same container. If grown in a hanging basket, it will spill over and trail to a certain extent. Given ample sunlight and well-drained soil, it requires almost no attention and spreads itself very easily. It will even grow in cracks of a wall, or in the spaces between the stones of paths. If planted in the crevices, it will add wonderful colour to rock gardens. It is drought-tolerant, but flowers best with regular watering. Over-watering, however, will cause root-rot.

It can be propagated from seed, but the seeds are very tiny, and are best mixed with sand to get an even spread when sowing. Most nurseries sell ready-to-plant seedlings. Stem cuttings are easily struck, simply by pushing them into the soil. In warm climates, moss-rose will usually self-seed.

 

Photographs taken Picnic Bay, 2010
Page last updated 18th March 2019