TAKING TO THE WATER
Ponds, streams and bogs can give your plot a splash of colour
WHENEVER I visit a garden with natural water, I go green with envy. Imagine a gently flowing brook or a natural, spring-fed pond as your central feature. Natural water courses look ravishing in summer when colourful wildflowers line their banks. Fish shelter beneath floating lily leaves while dragonflies patrol the surface.
In the boggy zones, wetland plants hide the ugly mud with rich carpets of vegetation.
In a garden you can make a natural stream, pond or bog look even prettier than in the wild. Choose the right plants and it becomes a charming feature from March to November.
Yellow celandines and mauve cuckoo flowers could open a show which could end with colourful astilbes. In my parish, the fenland dykes are lined with handsome water plants. Years ago, I filched slips of those, plus waterweed, for our garden pond. My foraging was only for the commonest plants which line the frequently dredged dyke.
GETTING IT RIGHT ...
IN A bog garden, drainage rules don’t apply. Water stays put or seeps away slowly, so you need plants which love saturated soils. Luckily, there are plenty, both native and exotic. Many are invasive or become too large, so choose cautiously.
Huge, rhubarb gunneras are impressive, as are big-leaved skunk cabbages. But both are highly invasive. Our native phragmites reeds are graceful but also invasive, as are most sedges. So go for manageable varieties such as Bowles Golden Sedge, Carex elata Aurea.
For foliage, most hostas love damp conditions. Among moisture-loving ferns, Matteuccia struthiopteris resembles lacy green shuttlecocks. Royal Fern, Osmunda regalis grows large but is non-invasive.
Native damp-lovers include pink ragged robin, yellow king cups and pink Geum rivale for spring to summer. Those could precede exotics as candelabra primulas such as red P. japonica or orange P. bulleyana.
Tall Lobelia cardinalis flowers later, with vivid scarlet spikes, and look lovely near big-leaved hostas. More gorgeous still are
Japanese water irises, I. ensata. Some of this variable group can be fussy, but the huge blooms make them so worthwhile.
Gerald Darby has purpletinted leaves and deep blue flowers. That would team well with Holden Clough, whose yellow flowers have dense brownish-purple veining.
MAKE YOUR OWN
IN ANY garden a natural stream is an asset. Subject to river authority regulations, you can alter its course, slow the flow or widen it to create a swamp.
Even without natural water, you can still develop an attractive wetland feature. At its simplest, that could be a waterretaining depression or basin. But it should be at least 45cm at its deepest with sloping sides.
After smoothing bumps or irregularities, line the depression with a waterproof membrane. A pond liner is best, but heavy duty polythene can work.
If the levels are right, you’d have the makings of a shallow pond. Backfill the hole with soil, and it’s a potential bog. Before adding water, anchor the liner with paving slabs, turf or soil.
If large enough, your bog could even house a small pond. That would create a focal point. Thus, you’d have the beginnings of a wetland garden.