Calathea plant like being wet at all times and do not like being waterlogged. You should water them when the top inch of soil feels a little dry, every week or so, depending on the humidity and heat of your home. Always apply room temperature, filtered or distilled, water to avoid accumulation of minerals which may destroy leaves. In winter when growth is slow, reduce watering. The trick is to have a balance- neither to get the soil too dry nor to have too much drainage so that the roots rot.
