A garden oasis

PUBLISHED: 12:41 24 February 2015 | UPDATED: 12:41 24 February 2015

Marsh frog on a lily pad

Marsh frog on a lily pad


Creating a pond is one of the best things you can do for wildlife in your garden. Sarah Buckingham of the Herts and Middlesex Wildlife Trust says February is the perfect time to do it

Yellow water lilliesYellow water lillies

Our gardens have become increasingly important wildlife havens as the countryside around us is broken up by new building and infrastructure developments. With this extra responsibility on our green spaces, how can we improve the environment we offer our wild visitors? One fantastic solution is to add a pond. These watery oases support a greater diversity of life than any other garden habitat, and are one of the best ways to attract a wide range of wildlife. As well as insects, fish, amphibians and plants living in the pond, mammals and birds will come to drink and bathe. It may be cold outside, but February is the best time to grab a spade and get digging! The new pond will then be full of life come spring.


Choose a good spot

Think about how it relates to other wildlife features in the garden <bold> Log piles and long grasses provide cover for shy garden visitors. Nearby trees will drop large amounts of leaves into the pond, so avoid putting your pond too close to overhanging branches.

A nuthatch takes a dip in a pondA nuthatch takes a dip in a pond

Consider the amount of sun and shade Plenty of sunshine will warm the water and encourage plant growth. Semi-shaded conditions are fine, preventing the growth of excessive algae, as well as giving nearby cover for visiting wildlife.

Will you be able to see the wildlife? You might want to put your pond close to the house, so it can be viewed from inside. A flat, stable surface around it will make maintenance and viewing easier.

Allow for an overspill <bold> Make sure that any excess water can drain away without causing a problem.


Emperor dragonflyEmperor dragonfly

Designing your pond

Size <bold> While any pond will be of benefit, the larger it is, the better (although no pond is too small to be useful).

Shape <bold> Not critical, but is probably best kept simple.

Depth <bold> The deepest point should be a minimum of 75cm; this will allow hibernating amphibians and invertebrates to survive the coldest winters when the pond is frozen over. There should be a shelf about 20-30cm deep to place emergent plants on. Finally, there should be a gently sloping shallow area for bathing birds and to allow wildlife to get in and out. If a sloping side isn’t possible, provide a ramp in one corner.

Getting the planting right is key to a healthy pondGetting the planting right is key to a healthy pond


Fitting a flexible liner

There are several options for lining a pond including concrete, pre-formed fibreglass, puddled clay and flexible liners (the most common option as they adapt to any shape or size).

Dig a hole about 20cm deeper than required to allow for sand, matting and liner.

Calculate the size of the liner as follows: Length = length of pond + (2 x maximum depth) + 1m edging. Width = width of pond + (2 x maximum depth) + 1m edging

Spread a layer of sand approximately 5cm thick in the hole. This will protect the liner. You may wish to lay protective matting, which can be bought when you purchase the liner. Alternatively, use a piece of old carpet or underlay.

Lay the liner across the hole. Handle it gently and only tread on it with soft-soled shoes or bare feet. Weigh down the edges with bricks or pieces of paving slab.

Fill the pond. As the water level rises, the weight of the water will pull the liner into the contours of the hole. Do not cut off any excess liner until the pond is completely full. When full, cover the edges of the liner with turf or paving slabs.


Picking the right plants for your pond is vitally important as they provide oxygen, food and shelter for a range of wildlife.

Submerged oxygenating plants The least spectacular plants, but very important in keeping water clear, well oxygenated and low in nutrients. Go for water starwort, hornwort, water milfoil and curled pondweed.

Plants with floating leaves Rooted in deep water, examples include white and yellow water lily, broad leaved pondweed and amphibious bisort.

Emergent plants For planting in shallow water – flowering rush, greater and lesser spearwort, bur reed, water plantain, yellow flag iris, water mint, water forget-me-not, brooklime and water violet.

For marshy areas/pond edge Meadowsweet, purple loosestrife, lady’s smock, gipsywort, ragged robin and marsh marigold.

Avoid non-native species Use native plants as much as possible – exotic species could be invasive. Avoid: Australian swamp stonecrop, curly water weed, floating pennywort, parrot’s feather, water fern, water primrose and Canadian pondweed. These will soon take over and suffocate your pond.


Let wildlife move in

Once you have filled and planted up your pond, just wait. Wildlife will move in quickly! Avoid transferring frogspawn to your pond in spring, as this can spread diseases. The frogs and toads will find your new haven under their own steam. You will be amazed how quickly wildlife takes up residence in a new habitat.


Ponds and safety

Unless securely fenced off, a pond can be dangerous for young children. Constant supervision should be given to children in gardens with ponds. Do enjoy the wildlife sights and sounds with your children though.


Download The Wildlife Trust guide to wildlife gardening, which includes tips on creating the perfect pond, at hertswildlifetrust.org.uk/wildlifegardening

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