BOND WITH A POND!
Wildlife loves a home-made water feature — and so will you
MORE GARDENING — Page 88
WINTER is almost here and routine chores are running down. So now is an excellent time to start on new projects. Perhaps you’d like to replace an old fence, construct a coldframe or try something more ambitious?
My task is to make a new pond. It will need to look gorgeous and act as a wildlife haven, but, like any new feature, it must blend beautifully into the garden’s existing design.
Dragonflies and frogs visit us each summer, so I hope they’ll begin to breed. We’ll create a bog area nearby, partly to encourage them, but we also hope to grow a range of lovely wetland plants.
The pond will be roughly oval, occupying about 5 sq metres, partly in sun and part shaded. There’ll be a shallows for creatures to move in and out of the water and a deeper centre for water lilies.
Maximum depth won’t exceed 60cm and there’ll be a submerged ledge along some of the edges for marginal plants.
I’m assuming we’ll need a flexible Butyl pond liner. But the subsoil of our chosen site has a layer of impermeable blue clay. If that proves to be thick enough once we’ve dug the hole, it could be moulded into a naturally watertight basin.
FIRST STEPS
TO INSTALL a pond you need to know what you’re doing. My DIY skills run little further than changing a light bulb, so a contractor will do the tricky work.
If you build your own pond, remember that the sides must be dead level all round. You’ll need a spirit level and pegs for marking. When the pond is full, none of the liner should show above the surface. After levelling the site, dig out the area to a depth of 20cm to 25cm.
Next, mark out the 30cm wide marginals shelf before excavating the central area. Maximum depth can be 45cm to 60cm and the sides should be sloping.
Butyl liners are durable but easily punctured. Make sure the bed is baby-bottom smooth and clear of stones, roots or anything sharp. An underlay of sand or material such as old carpet will give further protection. When laying your liner, leave plenty of it spare on all sides so the levels can be fine-tuned. Finally, secure and conceal the liner edges under paving or turf.
We may sink a second liner to one side of the pond to create a bog garden.
WETLAND BEAUTIES
I WANT our mini-wetland to look natural. But wild marsh plants can be huge so I must choose with care. Rampant yellow iris, butterfly-attracting hemp agrimony and bull-rushes would be too big.
But there’ll be room for drifts of tall candelabra primulas in orange or yellow or ruby shades. I’ll place royal fern, Osmunda
regalis at the back and for spring, we’ll include native yellow-flowered kingcups and blue water forget-me-not.
Lilac cuckoo flowers can accompany variegated grassrush Acorus gramineus, with Bowles’ golden sedge Carex
elata Aurea behind. In the pond itself, avoid invasive alien plants. Submerged native oxygenators include
Potamogeton, Ceratophyllum or hornwort, Callitriche or starwort and water crowfoot.
In summer, a pond needs floating leaf cover. Water lilies provide that, but choose small varieties. I’ll grow bronze-leaved Nymphaea Sulphurea.