How to Grow Ice Plants UK

When to Plant Ice Plants in the UK

When to plant ice plants in the UK: in Southern England, sow mid May to mid June. Find your area in the table below.

Region	Sow
Southern England	mid May to mid June
Midlands	late May to late June
Northern England	late May to late June
Scotland	early June to early July

Southern England - detail & sources

PFAF: sow under glass in spring, transplanting out only after the last frost -- taken here as a mid-May to early-June planting-out window for southern England.

Midlands - detail & sources

Planting-out window shifted about a week later than southern England for a typically later last frost. PFAF's warning that this plant "will be killed even by a light frost" is a genuine limiting factor to respect here.

Northern England - detail & sources

Planting-out window shifted about two weeks later than southern England for Northern England's later last frost date -- the same zero-frost-tolerance caveat applies.

Scotland - detail & sources

Planting-out window shifted about three weeks later than southern England for Scotland's later, cooler spring. Honest caveat: a plant killed outright by a light frost gives Scottish gardeners a genuinely short outdoor season here.

Quick Facts

Factor	Value
Drainage	Prefers well-drained soil (PFAF); tolerates light/sandy, medium/loamy or heavy/clay soils, mildly acid to mildly alkaline, and genuinely saline conditions -- PMC: irrigation up to 35 dS/m (roughly seawater salinity) showed no adverse effect on biomass.
Lifecycle	PFAF: a true perennial in its native range, but "not very hardy in Britain and will be killed even by a light frost" -- grown here as a half-hardy annual, sown under glass and set out after the last frost.
Edible parts	leaves, stems

At a Glance

Growth Stages

Stage	BBCH	Notes
Sowing under glass	0	PFAF: sow in spring under glass, only just covering the seed. Seedlings are prone to damping off, so avoid overwatering and keep them in a very sunny, well-ventilated position.
Pricking out and transplanting	2	PFAF: prick out seedlings into individual pots once large enough to handle, and do not plant out until all risk of frost has passed -- the plant "will be killed even by a light frost."
Establishment and growth	3	PFAF: grow on in full sun -- "cannot grow in the shade" -- in well-drained soil; genuinely tolerant of poor and even saline ground once established. PMC: independently confirms strong salt tolerance, with irrigation up to 35 dS/m (roughly seawater strength) showing no adverse effect on biomass.
Harvest	8	PFAF: pick the thick, succulent leaves and stems through summer as needed, eaten raw or cooked as a spinach substitute. First frost ends the season for this half-hardy annual.

Harvest & Storage

When to pick: PFAF: pick leaves and stems as needed once plants are established and growing strongly through summer -- they are thick and succulent with a slightly salty tang, best used while young and crisp.

Storage

Best eaten fresh, as for other tender succulent salad leaves; PFAF also notes the leaves can be pickled.

Diseases

Damping-off (seedling collapse)

Rhizoctonia solani

Damping-off (seedling collapse at soil line); Wilting with chlorotic, dropping leaves

PFAF: young ice plant seedlings are prone to damping off -- avoid overwatering and keep seedlings in a sunny, well-ventilated position.

Root rot (unspecified)

PFAF: young plants are also prone to root rot; the pathogen is not specified, so kept as a generic entry rather than a fabricated species.

Ice Plant, a Salt-Tolerant Succulent Salad Green

Thick, succulent leaves

PFAF: leaves and stems are thick and very succulent, with a slightly salty tang -- eaten raw or cooked as a spinach substitute.

A low, spreading habit

PFAF: a low, spreading plant reaching only about 0.1m (4in) high but spreading to around 0.5m (20in) across.

At home on poor, saline ground

PFAF: tolerates light, medium or heavy soils and genuinely saline conditions -- confirmed independently by a peer-reviewed trial finding irrigation up to 35 dS/m (roughly seawater strength) had no adverse effect on biomass.

The glistening cells behind its name

The tiny, glistening, water-filled bladder cells covering the leaves and stems are what give this plant its common name -- they catch the light like scattered ice crystals.

A frost-tender seedling

PFAF: sow under glass in spring and don't plant out until all frost risk has passed -- this plant "will be killed even by a light frost."

Full sun only

PFAF: the plant cannot grow in shade and needs a full-sun position to thrive.

Grown commercially as a leafy vegetable

PFAF: leaves are eaten raw or cooked as a spinach substitute, or pickled -- increasingly sold fresh as a novelty salad crop in some markets.

A hygrochastic seed capsule

Like other Aizoaceae, ice plant capsules open only when wetted by rain, releasing seed at the moment conditions are right for germination.

Seed chambers revealed

The opened capsule shows the individual seed-holding chambers, each releasing its seed only once moistened.

References

1. Plants For A Future (PFAF) - Mesembryanthemum crystallinum

   Habitat: maritime sands and salt marshes, South Africa; naturalised southern Europe. Hardiness: USDA zones 8-11, UK hardiness zone 9 -- "not very hardy in Britain and will be killed even by a light frost," grown as a half-hardy annual. Soil: light/sandy, medium/loamy or heavy/clay, prefers well-drained, tolerates mildly acid to mildly alkaline and saline soils. Sun: full sun only, "cannot grow in the shade." Moisture: prefers dry or moist soil. Propagation: sow spring under glass, only just covering the seed; prick out into individual pots; transplant outdoors after the last frost; seedlings prone to damping off, avoid overwatering, keep in a very sunny, well-ventilated position. Size: perennial in native range, growing to 0.1m height by 0.5m spread. Edible use: leaves and stems eaten raw or cooked as a spinach substitute, thick and succulent with a slightly salty tang; also pickled or used as a garnish; fruit and seed also used. Medicinal use: demulcent and diuretic, used for inflammation of pulmonary and genito-urinary mucous membranes. Pests/diseases: young plants prone to root rot and damping off.

2. PMC (peer-reviewed journal, hosted by NCBI/National Library of Medicine) - Growth parameters, phytochemicals, and antitumor activity of wild and cultivated ice plants (Mesembryanthemum crystallinum L.)

   Controlled cultivation trial (soilless system, LED lighting, growth chambers) comparing wild (Almeria, Spain, coastal) and cultivated ice plant. Salinity: three nutrient-solution electrical conductivity levels tested (3.0, 4.0, 6.0 dS/m); separately reports that irrigation solutions of up to 35 dS/m had no adverse effect on biomass production, demonstrating strong halophyte tolerance. Temperature: plants grown at a constant 20-22°C. Light: LED lamp type affected biomass, with horticultural-spectrum lamps (NS1, AP67 Valoya) outperforming standard white LED. Yield: fresh plant mass 124-138g per plant depending on treatment, higher under higher salinity. Growing window: cultivation ran between May and July 2022 (about 2-3 months). Edible use: leaves described as having a "crispy, salty, and slightly sour flavor," eaten raw in salads, used to season seafood, or cooked. No pest or disease information given (a controlled-environment study, not an open-field/garden account).

2 independent sources are cited for this crop. Where they disagree - soil pH is the clearest case - every figure is preserved rather than averaged into false precision.