Polystichum aculeatum aka Hard Shield Fern

Polystichum aculeatum, commonly known as the hard shield-fern, is an evergreen fern native to Europe. It thrives in upland regions of the British Isles and western France, benefiting from mild winters and moist summers. Although it can be found across most of Europe, it is absent in northern Scandinavia and northern Russia, and in the Mediterranean region, it is limited to high altitudes. This fern is often found steep slopes in woodlands and is considered an indicator of ancient woodlands. The fronds of Polystichum aculeatum are glossy dark green, measuring 30-90 cm in length. Typically drooping downslope, a mature plant usually has 3-8 fronds. These fronds are stiff and hard-textured, bipinnate in structure, with pinnae arranged opposite on the stalk. Each pinna is 3-11 cm long, featuring a large upward-pointing pinnule at the base, while the other pinnules decrease in size towards the pinna tip. The pinnules have bristly tips. Individual fronds have a lifespan of 1.5-2.5 years and remain attached to the rhizome even after withering. The round sori, which produce light yellow spores, are found in two rows on either side of the midrib of each pinnule. These sori are covered by a centrally-attached, umbrella-like indusium with fringed edges. The Latin specific epithet "aculeatum" refers to the bristly nature of this fern. Polystichum aculeatum is a popular ornamental plant in gardens and has been awarded the Royal Horticultural Society's Award of Garden Merit. As a houseplant, it requires ample water to thrive and prefers long-lasting, direct light within 1 foot of a window. It benefits from soil that retains moisture well. Repotting the plant when it doubles in size eliminates the need for additional fertilizers.