Wet soils are normally heavier, loamy or even clay, also peat soil and soil rich in humus, soil by watercourses and on swampy terrain. These are mostly less airy or even not airy enoguh for most plants, they are always wet or even saturated with water; water stagnates, only slowly flows away. Plants of such undergrowth do not tolerate drought, in neccessary need of permanent moisture, tolerate inundation, some can grow in shallow water (up to 5 cm in depth) or in garden bed, when watered regularly.