Overview

Asplenium antiquum 'Osaka' is a clump forming ferns in the genus Asplenium, part of the Aspleniaceae family, with evergreen foliage. It typically grows around 0.5-1 metres tall and 0.5-1 metres wide, reaching full size in around 5-10 years. Asplenium antiquum 'Osaka' grows best in partial shade, and tolerates loam soils and acid and neutral pH. Its UK hardiness is rated H6. Suggested uses include cottage and informal garden, city and courtyard gardens, flower borders and beds, ground cover and underplanting of roses and shrubs.

About

Asplenium antiquum 'Osaka' (spleenwort 'Osaka') is a clump-forming evergreen fern suited to houseplants or conservatory settings. It typically grows to between 0.5 and 1 metre in height and spread over 5 to 10 years. This cultivar thrives in partial shade with a west or east-facing aspect and prefers sheltered conditions. It grows best in moist but well-drained loam soil with an acid to neutral pH. 'Osaka' provides year-round interest, particularly in spring, summer, and winter.

About the genus

Asplenium is a genus of about 700 species of ferns, often treated as the only genus in the family Aspleniaceae, though other authors consider Hymenasplenium separate, based on molecular phylogenetic analysis of DNA sequences, a different chromosome count, and structural differences in the rhizomes. The type species for the genus is Asplenium marinum.

Wikipedia contributors, "Asplenium", CC BY-SA 4.0Asplenium

Growing conditions

Best soil and position for Asplenium

Sunlight
Partial shade
Soil type
Loam
Soil pH
Acid, Neutral
Soil moisture
Moist but well-drained
Aspect
West-facing, East-facing
Exposure
Sheltered
UK hardiness
H6

Plant details

Asplenium antiquum 'Osaka' size, habit and characteristics

Plant type
Ferns, Houseplants, Conservatory Greenhouse
Habit
Clump forming
Foliage
Evergreen
Height
0.5-1 metres
Spread
0.5-1 metres
Time to full height
5-10 years
Suggested uses
Cottage and informal garden, City and courtyard gardens, Flower borders and beds, Ground cover, Underplanting of roses and shrubs

Care notes

Pruning and caring for Asplenium antiquum 'Osaka'

Propagation
Division, Spores
Pest resistance
Generally pest-free
Disease resistance
Rust

Frequently asked questions

Where is the best place to plant Asplenium antiquum 'Osaka'?

Asplenium antiquum 'Osaka' prefers partial shade. It suits sheltered positions.

What soil does Asplenium antiquum 'Osaka' need?

Asplenium antiquum 'Osaka' grows best in loam soil. It prefers acid and neutral soil. Aim for soil that stays moist but well-drained.

How big does Asplenium antiquum 'Osaka' grow?

Asplenium antiquum 'Osaka' reaches a height of 0.5-1 metres and a spread of 0.5-1 metres. It takes around 5-10 years to reach full size.

Is Asplenium antiquum 'Osaka' hardy in the UK?

Asplenium antiquum 'Osaka' has an RHS hardiness rating of H6, meaning it is very hardy, tolerating -20 to -15°C across most of the UK.

How do I propagate Asplenium antiquum 'Osaka'?

Division, Spores.