Polystichum aculeatum - Hard Shield Fern

Polystichum aculeatum, also known as Hard Shield Fern or Prickly Shield Fern, is a very beautiful fern. This evergreen terrestrial species is one of the most ornamental in winter. It has an upright, majestic habit and large, tough, finely divided fronds of a dark and glossy green colour. In spring, pretty blonde crooks appear near the base, unfolding into young fronds of a tender green colour with a stalk covered in brown scales, growing in a regular crown. It is easy to grow in full light, in any cool, humus-rich or even slightly calcareous soil. It also grows very well in pots.

The Hard Shield Fern is a botanical species with a short, thick stump, native to Europe, widespread from the western part of the continent to the limits of Asia, present in North America and Africa, where it grows spontaneously in various habitats such as shaded slopes, ravines, and wet ditches. It is a perennial plant of the Dryopteridaceae family, closely related to the male fern. Polystichum aculeatum forms an upright, tall and wide clump, ranging from 60 to 80 cm (24 to 32 in), or even 1 m (3 ft) under very good conditions. The slightly arching fronds, with a leathery appearance, form a crown. They have a highly divided lamina with toothed pinnules, with the teeth ending in very fine prickers. The rachis (the "vertebral column" of the frond) is very scaly and brown. The sori (small spore sacs), brown when ripe, are produced on both sides of the pinnule veins, on the undersides. The emerging young crooks in spring are tinged with blonde.

The Polystichum genus comprises a very diverse and particularly decorative group throughout the year for most species and varieties. The Hard Shield Fern is a very hardy species that adapts to many cool and shaded situations, even on a limestone subsoil. We grow it among rocks in our shady and cool rockery. Its large glossy fronds allow for beautiful arrangements for festive tables, at a time of year when flowers are scarce. In the undergrowth, it can be associated with simple plants such as butcher's-broom, hollies, mahonias, or cotoneasters. In a shaded border, it can be neighbours with Hart's-Tongue Fern or a sturdy and undemanding conifer such as the Siberian cypress (Microbiota decussata). In a more refined border, it can accompany, for example, fuchsias, yellow loosestrifes, and bicoloured pineapple lilies. It will also thrive near a water feature, among candelabra primroses (Primula bulleyana) or Japanese primroses (Primula japonica).