(Editor's note: This article was originally published on June 11, 2009. your commets are wlcome, but please be aware that authros of previously published articles maynot be able to respond to your questions.)
The planter was in full sun and no supplemental irrigation was available. We knew we would have to water the plants by hand if nature didn't intervene and send rain. What was needed was a spot of color during the summer and fall that needed to be watered very little and that required minimal care. It would have to survive on its own during the summer since we wouldn't be there to care for it. Anyway, the children and I were busy learning about singular and possessive nouns and other matters of great importance, so we had little time for such pleasurable pursuits as flower gardening.
We decided that moss rose (Portulaca grandiflora) would be a good choice. After removing the weeds, we dug in a bit of peat moss and cow manure and followed it up with a light sprinkling of slow-release fertilizer. Then we planted several trays of the colorful flowers down the length of the planter.
Portulaca is a flowering annual that blooms throughout the summer. One-inch, roselike flowers of pink, white, yellow, orange, purple, scarlet, and combinations of these open in the bright light of day. Some varieties remain closed at night or on cloudy days. Inch-long leaves are somewhat succulent and cylindrical.
Portulaca was a perfect choice for the planter. We planted the plants about 8 inches apart, and they filled in and made a solid mass of color within a month or so. The plants were watered every day after lunch until they became established. Then they were left to fend for themselves.
Plants are easily started by seeds. Scatter seeds on the soil surface and make sure they have good contact with the soil. Keep damp until seeds germinate. Expect germination in 10-14 days. New plants can also be started from cuttings.
Several species of portulaca are in the trade. Portulaca umbraticola is the popular purslane that is grown in hanging baskets and gardens. It has broader, more succulent leaves than moss rose. P. oleracea, sometimes called pigweed, wild portulaca, little hogweed, and pusley, is the not-so-popular, weedy purslane that infests gardens and disturbed areas in most of the United States. Although it is edible and has medicinal applications, it is seldom planted in the garden. If a crop is wanted for adding to the salad, it should be planted in a container.
Some popular cultivars of P. grandiflora include 'Calypso', an F2 hybrid with double flowers, and 'Sundance' which remains open longer than some other cultivars. 'Afternoon Delight' and 'Cloudbeater Mix' stay open all day. If certain colors are wanted, look for the Sundial series, which offers plants in separate colors. Many other cultivars are available, and most of them are mixes of all colors.
In the Garden
Few plants are as well-suited to hanging baskets and containers in hot, sunny, sandy areas as portulaca. Rock gardens are also ideal places for these plants. They are an excellent annual groundcover, and they were a good choice for the raised-bed planter at school. For the rest of the school year and during the next one until Jack Frost came calling, the flowers were enjoyed by everyone who came within viewing distance of the planter.If you have a hot, sunny area and need a spot of color, you might choose portulaca. It is readily available in spring at almost any garden center. You will discover, and Dave's gardeners agree, that moss rose does not need a lot of fussy care. Plant it, and if you forget to water or fertilize, don't worry overmuch. It will most likely do just fine without you.
AT A GLANCE
Say: por-tew-LAK-uh gran-dih-FLOR-uh
Family: Portulacaceae (Purslane family)
Other names: Rose moss, portulaca
Zones: All zones
Light: Full sun
Water Use Zone: Low
Size: 5 inches by 2 feet
Soil: Sandy, well-drained
Salt tolerance: Excellent
Thanks to Delirious_kat, gardengrrl, and chicochi3 for their images of Portulaca.