How to Grow Sagina Plants

Guide to Growing Irish Moss and Pearlwort

Sagina are mat growing hardy perennial mosses that reach about 10 cm (4 inches) in height.

Sagina have lime green lance shaped leaves, and bloom in the summer carrying tiny white flowers.

Sagina subulata
Sagina subulata (Aurea); Golden Irish Moss) by darknesschildsin.

Their size makes them a great plant for using in rock gardens, as ground cover, and for the gaps in dry stone walls.

Some common names for Sagina include Irish Moss and Pearlwort.

Commonly Grown Sagina Species

Sagina procumbens

Sagina procumbens
Sagina procumbens (Procumbent Pearlwort / Birdeye Pearlwort / Matted Pearlwort), photograph by Andreas Rockstein; CC.

Sagina subulata

Sagina subulata
Sagina subulata (Irish Moss / Scottish Moss / Heath Pearlwort), picture by mrburnes99; CC.

Sagina Growing and Care Guide

  • Common Names: Pearlwort, Irish moss.
  • Life Cycle: Hardy perennial. Some annuals.
  • Height: Two to six inches (5—15 cm). Often prostrate.
  • Native: Northern hemisphere, Equatorial Africa.
  • Growing Region: Zones 5 to 9.
  • Flowers: Summer.
  • Flower Details: White. Tiny. Solitary, or as small determinate simple inflorescences (cymes).
  • Foliage: Herbaceous. Green, lime. Opposite. Lance-shaped. Whorled clusters.

  • Sow Outside: Cover seed. Start of spring - before the last frost, or towards the end of autumn.
  • Sow Inside: Germination time: two to four weeks. Temperature: 55°F (13°C). Seven or eight weeks before the expected last frost. Transplant outdoors following the last frost. Space at 2 to 8 inches (5—20 cm).

  • Requirements and care: Full sunlight or partial afternoon shade in hotter areas. Moist, sandy soil. Light soil, poor soil. Short-lasting perennial plant, replace regularly for best results. Propagate: by dividing in the spring in cooler areas or the autumn in warmer areas. Protect from aphids.

  • Family: Caryophyllaceae
  • Closely Related Species: Pinks and Carnations
  • Miscellaneous: Due to its small size Sagina subulata cv. Aurea (Scotch/Irish moss) makes a great plant to grown between cracks in paving stones.

How to grow Irish Moss and Other Sagina

The seeds of Irish Moss and other Sagina species can be sown outdoors either in autumn or the beginning of spring.

Once sown lightly cover the seed. Plants should be spaced about 10 cm (4 inches) apart unless it is a spreading variety, then they should be grown about 20 cm (8 inches) apart.

Irish Moss likes to be grown in sunny areas that have afternoon shade, and thrives in a moist, light, and sandy soil.

If starting off indoors then do so about 7 or 8 weeks before the last frost of spring.

It should take two or three weeks for the seeds to germinate at 12 degrees centigrade (54°F). Transplant them out after the last frost of spring.

Caring for Sagina

It is easy to care for Sagina plants. They like a moist soil, so water them frequently; also give them a regular feed.

It may be necessary to grow Irish Moss near plants that attract ladybirds as aphids love to feed on them.

I hope that you enjoyed this guide on how to grow Sagina. You may also enjoy the following growing guides: How to grow Dianthus plants and Sweet william.