The leaf blade is somewhat horizontal and triangular, pinnately compound at the base and pinnatisect from then onwards.

[citation needed] Phegopteris connectilis favors wet habitats: the sides of streams, areas with springs, coniferous swamps and eutrophic paludified hardwood-spruce forests (lehtokorpi in Finnish).

Unlike its close relative, Phegopteris hexagonoptera, which is terrestrial, this species is often epipetric as well as terrestrial, able to grow at the bases of rocks and in crevices of shady, moist rock walls.

[4] The plant demands fair nutrition from its seedbed and it does not like acidic ground.

[4] The phenolic compounds 2,4,6-trihydroxybenzoic acid-4-O-2′,3′,4′,6′-tetraacetylglucoside; 2,4,6-trihydroxybenzoic acid-4-O-2′,3′,6′-triacetylglucoside; 2,4,6-trihydroxybenzoic acid-4-O-3′,4′,6′-triacetylglucoside; 3-O-p-coumaroylshikimic acid; 2-(trans-1,4-dihydroxy-2-cyclohexenyl)-5-hydroxy-7-methoxychromone; kaempferol; and kaempferol-3-O-β-d-glucoside can be isolated from the methanolic extract of fronds of Phegopteris connectilis.