Dryopteris × complexa 'Robust'

Common Name: buckler fern 
Type: Fern
Family: Dryopteridaceae
Zone: 5 to 9
Height: 3.00 to 4.00 feet
Spread: 3.00 to 4.00 feet
Bloom Time: Non-flowering
Bloom Description: Non-flowering
Sun: Part shade to full shade
Water: Medium
Maintenance: Low
Tolerate: Rabbit, Drought, Heavy Shade


Easily grown in average, medium moisture, well-drained soils in part shade to full shade. Prefers moist, humusy soils that are rich in organic matter. Likes sun-dappled conditions. Surprisingly drought tolerant once established. Site in locations protected from strong winds to prevent damage to the fronds.

Noteworthy Characteristics

Dryopteris × complexa, commonly known as buckler fern, is a hybrid between D. affinis and D. filix-mas. It generally features the stronger fronds of D. affinis and the more finely divided fronds of D. filix-mas. Bipinnate upright arching fronds rise to 2-3' tall from an erect crown. Semi-evergreen in warm winter climates, but basically deciduous in the St. Louis area.

Genus name from Greek dryas meaning oak and pteris meaning fern in reference to the presence of some species of wood ferns in woodland areas populated with oaks.

The hybrid name complexa means "complex" in reference to the highly dissected fronds of this hybrid.

'Robust' typically grows 3-4' (less frequently to 5') tall. It is a vigorous grower (as the cultivar name suggests) which forms a substantial foliage mass of deeply divided, upright arching fronds which have a somewhat ruffly or wavy appearance. Fronds emerge light green but mature to deep green. Semi-evergreen in warm winter climates, but basically deciduous in the St. Louis area. Synonymous with and sometimes listed for sale as Dryopteris filix-mas 'Undulata robusta'.


No serious insect or disease problems.


Woodland or shade gardens.