Is Your Pond Ready For Autumn?

At this time of year, it’s worth spending some time preparing your pond for the colder months ahead. This will ensure that your pond plants and any aquatic creatures will survive the winter, and be ready to flourish next year. A few simple jobs now will make for much less effort when spring rolls around again. Here are some important jobs to get done.

Remove decaying vegetation

Chances are, there will be some fallen leaves in the pond, which can release harmful pollutants as they decay. If left, they will sink to the bottom and form a rotten sludge, which will make the pond shallower, and affect the balance of nutrients in the water. Therefore, it’s important to remove any fallen leaves and any other decaying vegetation.

If your pond is located near a tree, it may be worth putting a net over it as soon as the leaves begin to fall. Nets also protect the pond from predators, so if you have fish which have attracted the attention of a heron for example, a net would be a good idea.

Prep your pond plants

If any of your pond plants have become overgrown during the summer, trim them back, or remove them from their basket and divide them before replanting. Remember that most pond plants will naturally go brown and wither during the winter, but this doesn’t mean they are dead, so don’t dispose of them, just prune off the outer foliage.

For most varieties of semi-submerged marginal plants, you should cut down the foliage or stems to about six inches above the water level. There may be exceptions for certain species, so it’s best to check the care instructions or contact the nursery where you bought it for advice.

Most varieties of submerged or free-floating pond plant, such as Hornwort and starwort, are very hardy and should be fine during winter unless the pond is allowed to freeze solid. Some exotic free-floating species of aquatic plant may do better being removed from the water and kept in a container in a greenhouse over winter.

Add some evergreens

To add interest to your pond during winter, it’s good to include some evergreen or semi-evergreen varieties of pond plant. For example, Hard rush (Juncus inflexus), Soft rush (Juncus effusus), Corkscrew rush (Juncus spiralis, Fibre optic (Scirpus cernuus) and Common cotton grass (Eriophorum angustifolium) will normally stay green all year round. You may also decide not to trim back a seasonal marginal plant, if the stems or foliage add interest and texture to a barren garden in winter.

Guard against ice

It is important to make sure the entire surface of your pond doesn’t freeze over in cold weather, as this will starve the plants and any fish or wildlife of oxygen, and may upset the nutrient balance, as gases from decaying plants can’t escape.

Ice could also cause cracks in the lining of the pond, as the fluctuating temperature causes materials to expand and contract. It is very simple to prevent the water icing over, by placing a floating rubber ball in the pond, or a custom de-icing device. If the pond does ice over, defrost a patch with hot but not boiling water.