Mesembryanthemum crystallinum
crystalline ice plant
Southern Africa and the Mediterranean Basin
Overview
Mesembryanthemum crystallinum is a prostrate annual or biennial succulent forming mats 12-40 inches (30-100 cm) across and 2-6 inches (5-15 cm) high. The thick, fleshy, ovate leaves are 0.8-4 inches (2-10 cm) long and covered with large glistening bladder cells that resemble ice crystals or water droplets, storing water and salt. Stems are sprawling and fleshy, often tinged red in strong sun or salty soil. Flowers are 0.4-1 inch (1-2.5 cm) across, with many narrow white to pale pink petals, opening in spring and summer. The plant accumulates salt in its tissues and can switch to a water-conserving form of photosynthesis under drought and salinity. It completes its life cycle in one to two seasons, then dies, leaving salt-laden litter that suppresses other seedlings. Mats spread quickly on bare ground; the species is listed as invasive in coastal California and other Mediterranean-climate regions.
Native Range
Native to southern and eastern Africa and the Mediterranean Basin, on coastal sands, salt flats, and dry disturbed ground. Widely naturalized in California, Australia, Chile, and other regions with mild, dry-summer climates, where it grows on coastal bluffs, roadsides, and disturbed soils.Suggested Uses
Grown in coastal and dry gardens, rockeries, and containers as a fleshy groundcover, and historically gathered as an edible and a source of soda ash. Its self-seeding, salt-depositing habit spreads beyond plantings in mild climates, so it is restricted or discouraged in regions where it has naturalized. Suited to hot, sunny, low-water sites.How to Identify
Appearance
Size & Dimensions
Height2" - 6"
Width/Spread1' - 3'4"
Bloom Information
Detailed Descriptions
Flower Description
white to pale pinkFoliage Description
green to red, glisteningGrowing Conditions
Sun Requirements
Requires 6-12 hours of direct sunlight daily
• Full Sun: 6+ hours of direct sunlight
• Partial Shade: 3-6 hours of direct sunlight
• Full Shade: Less than 3 hours of direct sunlight
Water & Climate
Water Needs
Drought Tolerance
Drought tolerant when established
Care & Maintenance
Care Guide
Grows in full sun on sandy, sharply drained, and often saline soils. It tolerates salt spray and coastal exposure and needs little or no irrigation once established. Rich, moist soil produces lush growth and faster spread. The plant reseeds heavily and forms dense mats that crowd out other low plants, which leads to weedy spread in mild climates. There are few pests, though stems rot in waterlogged soil. Because it accumulates salt, the litter it leaves behind raises surface soil salinity.Pruning
No routine pruning is needed. Removing flower stalks before seed set reduces self-sowing and limits spread. Whole plants can be pulled out as they die back at the end of the season.Container Growing
✓ Suitable for container growing
Minimum container size: 2 gallons
✓ Toxicity
Non-toxicPlanting Guide
Planting Methods & Timing
Planting Method
direct sow
Direct Sow Timing
Sow in autumn or early spring in mild climates
Days to Maturity
70–140 days
Plant Spacing
18 inches