Why should you clean & maintain the pond?
Answer: To avoid algae and blanketweed growth next Spring.
Maintain the pond every Autumn:
- Net the pond to stop tree leaves falling into the pond water
- Remove any tree leaves that reach the water with a dipping net while still on the surface
- Cut back most upright marginal plant vegetation to 15cm (6") above the Winter water level
- Exceptions that should NOT be cut back in Autumn are illustrated below:
- Reduce low growing foliage - all old waterlily leaves & stems and trim some very long stems from rafting plants - not Potentilla palustris.
- Remove small amounts of accumulated silt by dragging a fine mesh net over the pond base.
You will get less algae bloom and blanketweed next Spring:
- If you clean out your pond little and often
- Remove all dying plant growth every Autumn to avoid rotting in Winter
- Do not allow a compost heap to build up on the base.
- Tidy the pond and remove excess plant growth.
- Reduce clump size of rafting stemmed plants but do not cut back completely. (In Autumn Myosotis scorpioides has black stems under the water. This plant is not dead - new shoots will appear from this black stem next Spring.)
- This allows maximum amounts of light to pass through the water to the submerged oxygenating plants in Winter.
- Leave all oxygenating plants in the pond in Autumn.
- You will get less algae bloom and blanketweed next Spring.
See below an 8ftx8ft pond: Photo after one season's growth on LHS and after pond clean & cutting back in Autumn maintenance on RHS.
Take special care when you clean and maintain the pond in Autumn:
- Be aware of any banned invasive plants in your pond.
- Check out our images on the Banned invasive pond plants page to identify all banned plants.
- Compost these carefully and never throw into natural waterways.
A smelly pond is in need of extra attention:
- This pond will have leaves & other plant growth or excess fish food sunk to the base of the pond
- The smell is from the layer of silt/sludge at the bottom of the pond resembling your compost heap!
- Caused by incomplete rotting of vegetation due to a lack of oxygen (anaerobic).
- If there is too much rotting and not enough oxygen in the water the rotting process (the Nitrogen Cycle) cannot complete.
- The result is a production of gases - methane and hydrogen sulphide (the smell of rotten eggs)
- These gases are deadly to fish and other living organisms.
To clean some of the pond base in Autumn:
- Remove the thick silt layer
- In a small pond use a fine, flat-edged dipping net which you can drag across the base of the pond and lift any silt into a wheelbarrow for redistribution on the veg patch as a good source of nutrients.
- Leave some silt for wildlife to hide in and as a source of nutrient for waterlilies next year.
- Do not be paranoid – you do not need to remove all the silt – look out for dragonfly and damselfly larvae using it as a hiding place and for other overwintering creatures like Great Diving Beetles.
- We recommend you net across one half of the pond floor one year and the other half the following year.
Alternatively, use Mud Muncher.
- An environmentally friendly solution to the build up of sludge and mud in ponds.
- A blend of live bacteria that contains no herbicides or pesticides.
- It digests organic matter such as fish waste, fallen leaves and decaying plant matter. These all cause the build up of sludge.
- Helps eliminate odours and reduces the need to clean out ponds and filters.
- Safe for fish, wildlife, pets and plants in the pond.
Major pond clean and maintenance:
- Do any major clean out or overhaul an old, neglected pond in Autumn
- Fewer wildlife species are in the water at that time of year.
- Be vigilant to check and replace any creatures that are removed from the water accidentally.
- Place creatures in a bucket of pond water, not tap water, until they are returned to the pond.
- Remove overgrown plants and decide how much of the clump should go back
- Would that plant benefit from being divided and potted into more than one basket? See our page Plant propagation
- Keep as much mature water as possible in clean dustbins to replace back into the pond after the clean out
- Top up with rainwater over Winter if possible.
Other Autumn pond tasks:
- Place any Half Hardy and Non Hardy plants into a greenhouse for protection.
- Place all waterlilies low enough in the water to be below any expected ice level in your area.
- Check any plants for duckweed and wash them clean before replacing them in the pond.
- Check for leaks or splits and weak spots in the pond liner and mend or add a patch of pond liner with waterproof adhesive
Spend more time now and see beneficial results next Spring.
- Useful long armed pond gloves to clean and maintain the pond in Autumn
- Cover the entire hand and arm in waterproof materials
- Either choose Small hand (size 8) or the larger hand size option
- No excuses! Clean out your pond now.
For related products - see below: