How to maintain Pond plants.
Essentially pond plants are herbaceous perennials and require only one cut in a season. This is usually done in Autumn, once they have all finished flowering. October to November are the best months for this.
Some prolific seeders like Marsh Marigold Caltha palustris, can be cut as soon as they have finished flowering. Usually April to May.
This reduces the amount of seed they produce.
They often send up a second show of flowers after being cut.
They are very decorative plants but can be a bit of a thug around a smaller pond, overpowering smaller more delicate plants like Ragged Robin Silene flos cucculi.
By the end of the year many of the plants in a pond will have spread an incredible amount. They are prolific growers.
Marginals are best cut to ground level around the pond edge. I use a scythe for this. working around the pond edge anti clockwise so that the cut vegetation is drawn away from the water by the scythe.
Emergent and deep water plants can also be trimmed (carefully) using a scythe or shears to as close to their base as possible.
In large ponds, where amphibians breed, it is best to only clear one third of the vegetation each year. As many amphibians (Adult male frogs and un metamorphosed juveniles) will hibernate in the mud at the bottom of ponds it is best practice to avoid too much disturbance.
Make sure as much of the cut vegetation as possible is removed and composted.
As mentioned, many pond plants are fast growers and need to be kept in check, otherwise they can smother the other plants and take over the pond.
Steer clear of exotic species if you can, as many have proved to be very invasive. Some, once available for sale, are now notifiable invasive plants, recognised as ecologically disastrous in UK waterways.
Native pond plants to watch out for are
Yellow Flag Iris,
Water Mint and
In this video I demonstrate how to clear dense mats of overgrown pond plants.
In this video you can see how thick some pond plants can become.
Their stems and roots forming dense mats on the surface as well as deep into the water.
With regular maintenance, as described above, this can be avoided.
Regular work is easier and lighter to carry out.
Rather than waiting several years and it becoming a hard heavy job.
In this video I demonstrate how to clear vegetation using a scythe.
Both in and around the pond.
Careful use of the scythe allows for quick work around the pond edge.
Once in the water I can use the scythe to snip water lilies and oxygenating plants at their base.
Once everything is cut, I can rake it out and compost it.
Pond plants compost incredibly well.
Sludge from the pond bottom is very nutrient rich and makes excellent fertiliser.