Garden Ponds: Why They’re Great For Wildlife and For You!
Written by Rebecca Carter-Whitehead
At only 2 and a half years old, my pond is a haven for me and my local wildlife.
Back in October 2021 as the world was slowly turning back to normal after the pandemic, my now husband and I invited friends round for what got dubbed a “pond digging party”. They came with pickaxes, spades, even a rail spike and a collie dog. Those who were not able to dig helped massively by making pot after pot of tea, and bringing out yet more biscuits, and even a first aid kit that was actually needed…
But the generosity of our friends meant that we got something I had always longed for: our very own pond! Well, it wasn’t a pond at first, more like a mud bath of a garden with a huge hole in it. The liner went down and the water butts were emptied, and as soon as the liner started to be dug in and the turf re-laid around the edge it suddenly took shape.
It’s evolved a lot over the last 2 years, but management for wildlife has always been at the forefront of my mind. This simply means: native plants only, limited pruning, and only removing things if absolutely necessary in autumn – I don’t like gardening so I love a low-maintenance feature! The pond has become a magnet for local wildlife; foxes, hedgehogs and bees love drinking from it, dragonflies and damselflies come to hunt and mate, bats in the evening love swooping over the water to catch flies, and this year we had the biggest influx of frogs I have ever seen! This of course has now brought the top of the food chain; a regular heron visitor. Watching all these waves of wildlife come and go through the seasons has given me so much joy, and it’s amazingly peaceful to go and sit by the water and watch the drama of natural life unfold. It allows such a welcome breathing space on days when my life can feel just a bit too much. A pond is not just a haven for wildlife, but a lovely calming influence on the mind as well.
The frogs certainly enjoyed the pond this March!
Building your own pond
I highly recommend the book “The Wildlife Pond Book” by Jules Howard (ISBN: 9781472958327). It’s a perfect step-by-step guide to all sorts of pond ideas from using a washing up bowl to large-scale installations. Everything we did was based on that book and a few other ideas we’d collected during our time as ecologists.
Placement
Ponds can be anywhere, and placement will dictate how your pond behaves as it establishes. Full sun might mean more aggressive algal blooms that require attention, while ponds in full shade under trees will be subject to collecting a lot of leaves. Partial shade is ideal, but if you do not have much choice with your placement any pond will still be beneficial to wildlife wherever it goes.
Size and Shape
The size and shape of the pond will dictate the success of a wildlife pond. Classic wildlife ponds have irregular edge shapes to them, such as a ‘kidney bean’ or ‘wavy-line’ shape. These outlines increase the perimeter of pond edges, allowing more space for edge-specialists such as common frogs in their tadpole stage.
‘Kidney bean’ shape on the left, ‘wavy line’ on the right
Ideally, it should be designed to retain a minimum of 20cm of water throughout the year. This can be achieved through the creating a scape to profile differing depths, and using natural bentonite clay to line the pond to aid in water retention and natural colonisation by plant and invertebrate species. Pond liners are also an option if clay cannot be used, but an effort must be made to ensure water is retained. At least some edges of the pond should slope gently making a seamless transition from wetland to deeper pond water, and to allow wildlife to escape the water. Avoiding steep sides anywhere is ideal.
Digging the pond
The topmost layer of soil dug out from the pond must not be used within the pond itself, as this is too nutrient-rich for a wildlife pond. Subsoil beneath this is best for profiling the pond prior to adding bentonite clay. Once the clay has been added it will need to be puddled. This is usually achieved by running vehicles forwards and backwards over the base of the pond to tamper down the clay and ensure it is watertight before filling - or in our case, lot and lots of jumping on it!
Should the pond be more than 10m2, the addition of islands created during digging will create places for nesting birds, as well as basking places for grass snakes. A pond of this size will also benefit from several deeper dug areas, to create lagoons of permanent water during hotter and dryer weather.
Before the sloping edges were profiled; one friend got a bit carried away with the pickaxe!
Filling the pond
Mains or waste water should not be used to fill the pond when digging is complete, as mains water often contains fluorides or other additions that are harmful to wildlife, where wastewater will be too nutrient-rich and cause algal blooms.
Rainwater is the best way to fill a pond, and this will naturally happen after digging is completed, but for large ponds this may take some time. Using water butts to supplement this process can help prepare the pond for planting.
Planting
Suitable aquatic vegetation planting is required to ensure the timely establishment of the pond. The pond should support a mix of emergent plant species and submerged plant species. How many depends on the size of the pond. Suitable examples of these include:
Emergent:
Yellow flag iris;
meadowsweet;
purple loosestrife;
rushes;
sedges;
greater spearwort;
water mint; and
water forget-me-not.
Submerged:
spiked water-milfoil;
whorled water-milfoil;
curled pondweed;
hornwort;
water starwort;
common spike-rush;
willow moss;
marestail;
water violet; and
water crowfoot.
This list is far from exhaustive, there are so many to choose from! The plants listed above are available in early autumn and spring, dependent upon species, and should be planted as soon as possible following the pond has filled sufficiently with water. A lot of the plants in my pond are pinched from local watercourses or given by neighbours – a quick little cutting that soon flourished! If I do this, I quarantine them in a bucket of rainwater for 1 to 2 weeks, to ensure disease or invasive animals are not accidentally being introduced.
The edges of the pond can be covered with planted coir rolls. These can also reinforce the banks if necessary for larger-scale ponds. Regular breaks in these rolls to allow access points should be included to allow for future management of the pond.
Yellow flag iris is so beautiful when it blooms.
Surrounding habitat
The surrounding habitats to the pond should be maintained with wildlife in mind. Ideally, the grassland should not be mowed too regularly to allow a transition from the emergent water plants to the surrounding habitat.
Hibernacula in the form of log or rock piles, or a compost heap can greatly benefit wildlife utilising the pond, particularly reptiles and amphibians.
Invertebrates also benefitting from the installation of the pond can be provided for with the addition of solitary bee hotels.
Lighting should ideally not be used, but it must be kept to a minimum if required for safety purposes. The use of solar-powered lights on timers can ensure lights are not excessively bright or left on for long periods of time.
A fence may be installed around the pond if there are safety concerns (e.g. small children or pets). The fence should still provide adequate space for wildlife to be able to access the pond; picket fencing is a good option for this.
I’ve had lots more life in my bee hotels since adding the pond!
Managing an established pond
Fish should not be introduced to the pond, and ideally it should not contain any pumps, as wildlife mortalities can occur.
Algal blooms may occur on occasion in the first few years of the pond’s creation. These are due to nutrient imbalances while plants establish. They can be managed with the additional of barley straw to the water. The cheapest way to do this is buy rabbit bedding, and the straw can be clumped into nets (e.g. laundry nets) and added to the water for approximately 4 weeks (or 2 weeks in warmer weather, if the water temperature is consistently 20∞C or above). Should filamentous algae occur such as blanket weed the majority can be removed by hand before the addition of barley straw. The blanket weed and (barley straw once it is done) can be left on the side of the pond for 24 to 48 hours to allow any hitchhiking pondlife to make it’s way back to the water before you dispose of the rubbish.
The management of pond plants and removal of detritus, such as fallen leaves, should occur in the autumn when most species have finished breeding or emerged from the pond, but have not yet entered winter hibernation. This means any animals disturbed by maintenance will be able to move themselves to safety. Any removed plants or detritus should be left next to the water’s edge for 24 to 48 hours to allow any animals to move back into the water, it is disposed of. This sort of work weather it is plant pruning or de-silting should ideally occur by hand to minimise damage to the pond and injuries to animals.
Desperate times call for desperate measures!
Perseverance through patience!
Did you know “new pond syndrome” is a noted phenomenon? This is when someone has put the effort into cultivating their own pond, and while it establishes during the first few years all you want to do is keep fussing with it. The internet is full of helpful groups and forums that can answer questions, but usually the best answer is leave it be and let nature do it’s thing.
You’ll soon find that your pond will balance as plants establish, and you’ll only become more and more fascinated by what shows up seemingly on its own. Nature is magic, and you’ll fall in love with your pond as I have mine.
