Correct watering of ornamental bushes in winter

Dear Ms. S., basically evergreen plants are more at risk from frost drought than deciduous plants, and in turn evergreen plants with leaves are more at risk than those with needles. The reason for this is simply that these plants evaporate water from their leaves or needles, but are unable to draw in more water from the frozen ground. Therefore, plants in pots are affected more quickly than those which are well-rooted in the ground. As a precaution, it is good to provide the plants with a large portion of water in autumn (ten to twenty litres per square metre, depending on the soil moisture), allowing them to stock up on their reserves prior to the frost setting in. Over the course of the winter, you can provide water on frost-free days as required. Pot plants which don't receive any precipitation have to be regularly inspected and watered as necessary. In my experience, pot plants which do receive precipitation generally have to have water drained out of them so that eastern teaberry, skimmia, ivy, pansies & co. do not become waterlogged. Typical symptoms of dryness on evergreens (such as drooping leaves on cherry laurel, rolled leaves on rhododendrons, flattened leaves on the hellebore) are often not dryness at all, but rather caused by the frost (and are therefore self-protection against dryness). After the frost, these symptoms disappear – as long as it isn't necessary to water them after all.