Pots and Containers in Winter

Looking After Outdoor Winter Pots and Containers

Ceramic and terracotta pots may crack in the freeze thaw temperatures that happen in winter. If it is a favourite, it may be best to empty out the pot out and move it into a dry area in a shed or under the house.

Check outdoor potted plants to ensure their drainage holes are not blocked with root growth as this can cause excess water retention and lead to root rot. If roots are coming through the drainage holes, repot into a larger sized pot.

Sit outdoor containers on 'pot feet' or use plastic milk bottle tops or pieces of tile or wood. Raising the container just a few centimetres above ca old damp surfaces will help water drain freely and prevent water logging.

Containers will still need watering, just less often. Check the surface of the potting mix, especially during mild spells. If the soil gets completely dry, the plants can dry out and die.

Position containers where they will get as much light as possible during the winter months to keep the foliage green and healthy. Summer positions may not work as well when the sun is lower in the sky and casts a longer shadow. Nearby trees, fences or retaining walls may cast shadows that aren’t there at other time of the year.  Avoid a position that gets a lot of wind as this can increase the drying effect and the cold damage.

Plants will grow very little through winter. And it is not necessary to fertilise them. When active growth begins in the spring, start feeding the plants again.

Overwintering Pots of Existing Plants

While many plants will appear dormant in winter, their roots are still alive and need protection.

Move existing tender or half hardy potted plants into a conservatory or glasshouse or the protected side of the house or under the eaves. A temporary roof of clear plastic can be used to cover them. A citrus tree is a good example of a potted plant that will need to be protected.

For extra sensitive plants, consider potting them into bigger containers which will offer more cold protection to the roots than what smaller pots can provide. The container can be wrapped with hessian or sunk into the ground as the soil in the pot will freeze harder than the soil in a garden bed.

Group multiple containers together to keep them warmer.

Planting Pots for Winter Interest/Colour

Fill empty containers with Alyssum, Calendula, Cineraria, Hellebores, Primroses, Violas, Polyanthus, and Violas to provide a splash of colour.

Start with good-sized plants and plant them close together to fill up the pot. Always use fresh potting mix with a good open structure that will warm up quickly and not get waterlogged.

Good evergreen shrubs for containers, with the bonus of colourful flowers from mid winter to early spring, include Azaleas, Camellias, Daphne, Hebe, Leucadendron, or Manuka.

Box can be topiaried into interesting shapes to provide interest.