Overview
Thelypteris palustris is a fern in the genus Thelypteris, part of the Thelypteridaceae family. It typically grows around 0.8 m tall. Thelypteris palustris grows best in full sun, and tolerates most soils. Its UK hardiness is rated H7. It is native to eastern North America and Eurasia.
About the genus
Thelypteris is a genus of ferns in the subfamily Thelypteridoideae, family Thelypteridaceae, order Polypodiales. Two radically different circumscriptions of the genus are in use as of January 2020. In the Pteridophyte Phylogeny Group classification of 2016, the genus is a very small one with about two species.
Wikipedia contributors, "Thelypteris", CC BY-SA 4.0 — Thelypteris
In the garden
A widespread wetland species, Thelypteris palustris (marsh fern) occurs across eastern North America and Eurasia and is adapted to persistently damp conditions. In cultivation it reaches roughly 0.8 m, with fresh fronds appearing through spring and holding through summer. Its natural affinity is for ground that remains wet rather than bone dry. Choose a site in full sun where the soil will not dry out; the plant accepts sandy, loamy or clay substrates provided they remain moist or wet, and it will also tolerate soils described as moist but well‑drained. Planting on the lower edge of a bog garden, the margin of a wildlife pond or a damp border gives the moisture it needs while allowing the fronds to show. It is fully hardy (H7), equivalent to USDA 4–8, so it will survive normal UK winters without special protection. Keep soil consistently damp during establishment and avoid siting in drought-prone raised beds. In planted schemes use it where upright, spring–summer fronds can form a mounding clump at the water's edge or beside a wet path, reaching about 0.8 m tall and providing structural green through the growing season.
Growing conditions
Best soil and position for Thelypteris
- Sunlight
- Full sun
- Soil type
- Sandy, Loamy, Clay
- Soil moisture
- Moist but well-drained, Wet
- UK hardiness
- H7
Plant details
Thelypteris palustris size, habit and characteristics
- Plant type
- Fern
- Height
- 0.8 m
- Native to
- eastern North America, Eurasia
Frequently asked questions
Where is the best place to plant Thelypteris palustris?
Thelypteris palustris prefers full sun.
What soil does Thelypteris palustris need?
Thelypteris palustris is adaptable and grows happily in most soil types, including sandy, loamy and clay. Aim for soil that stays moist but well-drained to wet.
How big does Thelypteris palustris grow?
Thelypteris palustris reaches a height of 0.8 m.
Is Thelypteris palustris hardy in the UK?
Thelypteris palustris has an RHS hardiness rating of H7, meaning it is fully hardy throughout the UK, tolerating temperatures below -20°C.
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