Wet heath is typically found on acidic, nutrient-poor substrates, such as shallow peats or sandy soils with impeded drainage. In Wales, wet heath occurs in areas with a moderate to high rainfall and is dominated by cross-leaved heath (Erica tetralix) and ling (Calluna vulgaris) typically accompanied by abundant deergrass (Trichophorum cespitosum), purple moor-grass (Molinia caerulea) and bog mosses (Sphagnum spp). The habitat often occurs with transitions to stands of humid and dry heath and to soligenous and topogenous mire habitats.

Several internationally important vascular plant and bryophyte species, especially those with an oceanic or Atlantic distribution, are well represented on wet heaths in the UK.