Sizzling ice plants

The other day I posted a photo of Cooper’s hardy ice plants (Delosperma cooperi) nestled against a clump of Cape balsam (Bulbine frutescens) and Jerusalem sage (Phlomis fructicosa). The color of these ice plant flowers is so intense, it looks almost fake.

Delosperma cooperi, flowers open

But like so many plants commonly given the moniker “ice plants,” Delosperma cooperi produces flower colors that border on the fluorescent. If they didn’t close up at night, they might light up your entire yard!

This is what the same clump looks like in the morning and evening:

Delosperma cooperi, flowers closed

But when there’s sun, the petals open up to reveal a cheery yellow center.

Delosperma cooperi

Delosperma cooperi

The default color of Delosperma cooperi—hardy to zone 5 and hence suited for most of the continental U.S.—is what I call magenta (other people call it purple or fuchsia). More recently a salmon-colored cultivar called ‘Mesa Verde’ was introduced. I planted one last year but it hasn’t produced any flowers yet so I can’t show it to you. (Plant Delights has a good photo on their web site.)

Other Delosperma species also flower in yellow, such as this Delosperma nubiginum I photographed at Annie’s Annuals. A few of those will come home with me the next time I go.

Delosperma nubiginum, just starting to flower

Last fall I bought an unlabeled flat of ice plants on closeout. I paid around $7 for 32 plants. I didn’t know with certainty what they were but the price was right. I had holes to fill in the planting strip outside the front yard fence so I had nothing to lose. They started to flower about a week ago, and after our recent trip to Alcatraz I recognized them right away. They are what Alcatraz inmates used to call “Persian carpet,” Drosanthemum floribundum.

Drosanthemum floribundum on Alcatraz

This is what a clump looks like in the morning and evening…

Drosanthemum floribundum, flowers closed

…and during the day (provided there is plenty of sun so the petals open up):

Drosanthemum floribundum, flowers open

Drosanthemum floribundum

Some interesting side notes:

In addition to Delosperma and Drosanthemum, the name “ice plant” is also used for the sea fig (Carpobrotus chilensis) commonly found along the shoreline on Central California’s Monterey Peninsula, the closely related Hottentot fig (Carpobrotus edulis), as well as many other plants in the genera Lampranthus and Aptenia. Confusion reigns supreme!

Many gardeners on the California coast lump all ice plants together under the moniker “mesembryanthemum.” Today, the genus Mesembryanthemum only contains a few ice plants rarely seen outside South Africa. However, in the past it also contained the ice plants so ubiquitous along the California coast, especially the invasive sea fig, Carpobrotus chilensis, which in spite of its species name is native to South Africa, not Chile. It has become such a common sight that many people—including gardening web sites—think it’s a California native. Massive efforts have been made in the last 20 years to eradicate Carpobrotus chilensis and edulis so native plants have a chance at a comeback. While ecologically sound, this hasn’t been an easy sell to the public since in a floral beauty contest Carpobrotus would beat many coastal natives.