What soil does Irish moss grow in?

It tolerates these soils: average garden soil, sandy, acidic.

Hardy down to -34 °C (USDA zone 4, RHS H7). It gets through winter in every part of the country.

When does Irish moss flower?

Flowering: May–August, white.

How much water does Irish moss need?

Water need: medium. Drought tolerance: low.

Irish moss

Sagina subulata

Irish moss (Sagina subulata) is a ground cover plant. Light: full sun, part shade. Hardy down to -34 °C. Drought tolerance: low. Sold in local shops from about €9.

Illustration of Irish moss — An illustration of the typical shape of the mature plant, not a photo.

What it's good for, and what it isn't

A ground cover that forms a moss-like evergreen cushion only a few centimetres high, dotted with tiny white flowers in early summer; it is also sold in a golden-leaved form. It suits the gaps between pavers and stepping stones, rock gardens and containers, and tolerates being stepped on now and then, but it cannot be used like a lawn. It asks for evenly moist yet free-draining soil and, in hot areas, a spot with shade at midday: it suffers equally from drying out and from standing water.

Watch out for

In the hot, dry summers of Central Europe it browns and thins out in patches in full sun and dies without watering; the parts that survive usually green up again in the cooler autumn weather. Winter wet and overwatering cause brown, rotting patches just the same, and it can scorch in dry frost without snow cover. With time, especially with too much feeding, the cushion humps up and lifts off the soil: press it back down, or pull it apart into smaller pieces in spring and replant them. Weeds have to be picked out by hand because it does not suppress them. Slugs and aphids can attack it.

Key facts

Light: Full sun, Part shade
Water need: Medium
Care: Medium
Size after 10 years: 5 cm × 30 cm
Hardiness: down to -34 °C
Foliage: Evergreen
Flowering: J F M A M J J A S O N D May–August, white

Group	Ground cover
Light	Full sun, Part shade
Size after 10 years	5 cm × 30 cm
Ultimate size	2–10 cm × 15–50 cm
Hardiness	down to -34 °C (USDA 4, RHS H7)
Soil	Average garden soil, Sandy, Acidic
Foliage	Evergreen
Flowering	May–August, white
Water need	Medium
Drought tolerance	Low
Maintenance	Medium
Root aggressiveness	Low
Suckering	no data
Spreading	Low
Distance from buildings	no data
Distance from paving	no data
Litter	not typical
Planting distance	15 cm
For dogs	no data
For cats	no data
For children	no data
Typical price	from about €9

Toxicity data is for information only. If your pet or child has eaten a plant, contact a vet or a doctor.

Sizes and prices available

The same plant is sold as a small pot and as a specimen several metres tall, and the price follows. Prices are rounded and for guidance only.

Size	Typical price
10-15 cm	approx. €9

Frequently asked questions

Data updated: October 8, 2026 · How our data is made

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