Flower growing guide
Ice plant
Delosperma cooperi · Aizoaceae
Sun
Full sun
Season
Warm
Maturity
1 to 2 years
Water
Low
Soil pH
6.0 to 7.5
Spacing
12 to 18 in
Planting ice plant
Plant nursery starts or divisions in spring once the soil warms, in the sunniest, best-drained spot available. Ice plant dies from wet ground faster than from cold, so a slope, rock garden, gravelly path edge, or raised bed beats a rich flat bed every time. Hardy ice plants overwinter in roughly zones 6 to 10, with newer hybrids pushing into zone 5 where winters stay dry; give plants at the cold end a sheltered spot and sharp drainage. Space starts 12 to 18 inches apart and they knit into a solid mat by the second year.
Planting details
- Spacing: 12 to 18 inches; a mature plant spreads to about 24 inches
- Set the crown at or just above soil level, never buried
- Gravel or grit mulch keeps the crown dry through winter
- Stem cuttings root quickly in warm weather; growing from seed is slow
Growing requirements
Full sun is not negotiable; ice plant in shade turns thin and leggy and barely flowers. It wants lean, sharply drained soil such as sand, gravel, decomposed granite, or rocky ground, and unamended clay is the usual killer. Soil pH 6.0 to 7.5 suits it. Water to establish the first season, then sparingly; established plants sail through weeks of heat and drought that flatten ordinary perennials. Skip rich soil and fertilizer, which push soft growth that rots at the first hard rain.
Harvesting and care
Bloom runs from early summer into fall where the plant gets full sun, with each daisy like flower opening in light and closing at night. The mat stays semi-evergreen in mild winters and can look tattered after hard freezes; wait for new growth in spring before trimming dead patches rather than cutting early. Stems that touch down roots can be lifted and moved to fill gaps or start a second bed. In containers use a gritty cactus mix and water far less than neighboring pots.
Common mistakes
- Wet soil in winter, which rots the crown even inside its hardiness range
- Planting in clay or low spots where water sits after rain
- Part shade, which produces a sparse leggy mat with few flowers
- Regular watering or rich feeding, which grows soft tissue that collapses
- Confusing hardy delosperma with Carpobrotus, the invasive iceplant of the California coast
Companion plants
Ice plant belongs on the driest edge of the garden with other sun lovers that hate wet feet: upright sedum, lavender, creeping thyme, and ornamental grasses. It also handles spots nothing else tolerates, like the strip along hot pavement and south-facing rock walls. Keep it out of irrigated beds and away from lush companions that need steady moisture, because the water that keeps them happy is what rots delosperma.
Varieties worth growing
- Delosperma cooperi: the standard hardy ice plant; magenta flowers on a mat a few inches tall
- Jewel of Desert series: compact cultivars in bicolor pinks, oranges, and yellows
- Fire Spinner: orange petals around a magenta ring; a Plant Select introduction
- Delosperma nubigenum: yellow flowers and the hardiest of the group, often listed to zone 4 or 5
Frequently asked questions
Is ice plant invasive?
Hardy delosperma spreads into a mat but is not considered invasive in gardens. The notorious invasive iceplant of coastal California is Carpobrotus edulis and its relatives, a different plant entirely.
Why did my ice plant die over winter?
Winter wet rather than cold. In zones 6 to 8 it shrugs off hard freezes where drainage is sharp and dies in soggy ground, so gravel mulch and a raised or sloped site matter more than mulch depth.
Does ice plant bloom all summer?
Yes, in full sun it flowers from early summer into fall. Individual blooms open in sunshine and close at night and on cloudy days.
