Ditch It! Ornamental & Flood Prevention Feature for Your Garden

Fifty years ago, ditches were a feature of everyday life; few roadsides were without them, and they formed an essential means of land drainage across Britain, protecting fields and houses from sudden floods. Since then, in many parts of the country, they seem to have been largely ignored – at least until now.

Driven by the growing need for sustainable urban drainage and the memories of thousands of acres of flooded land last winter, they seem to be making something of a come-back – and the good news is, they can make a perfect addition to any pond-enthusiast’s garden.

Functional and Ornamental Flood Prevention

The beauty of the back-garden ditch is that it is functional as well as ornamental, especially if you live in a high-rainfall area, or your ground is particularly prone to water-logging. If there’s a low-lying, problem area in your garden that always seems to be soggy, then you already have an ideal site – but even if nature hasn’t provided anywhere quite so obvious, you can still have your ditch.

Slowing the Flow – Flood Prevention

Before you begin digging, it’s worth stopping for a moment or two to understand how ditches do what they do.

Old-fashioned drainage ditches generally took surface run off and simply channelled it away to somewhere else – often into storm drains or natural water courses or onto unused land. Clearly, that’s not much of an option in the setting of an ordinary garden and in any case, your next door neighbours are hardly going to appreciate the instant influx of hundreds of gallons of ‘your’ water onto their lawn!

The ornamental ditch is best described as a kind of ‘blind’ ditch; it does not have an out-flow, but acts as a collection point, slowing the flow of water across the ground and giving it more time to percolate naturally into the soil, rather than rushing away and potentially causing flooding elsewhere.

Wildlife Benefits

It also represents a very special habitat for wildlife and one that has become rather rare in nature, especially since changes in agricultural practice have largely seen the demise of temporary ponds.

Some of the creatures likely to be encountered in the ditch are different from those to be found in a permanent pond, but a surprising range of familiar characters can put in an appearance from water-boatmen and pond skaters to frogs and toads.

Since they are not tied to the pond, in the way dragon-fly nymphs or fish are, the cast list tends to change along with the conditions in the ditch, with new arrivals coming and some of the previous residents going. It makes it perfect for mini-beast hunting if your young Attenboroughs need entertaining in the school holidays, because as Forest Gump put it, “you never know what you’re gonna get.”

Building the Ditch

Where you build the ditch is largely down to personal taste and the design and nature of your own garden. If your land is prone to getting water-logged, the right site is likely to suggest itself; if not, then you have more freedom over where you install the new feature, although obviously it should be at or near the lowest point of the ground if it’s going to be able to do its job properly.

In gardens with a high level of clay in the soil, in many cases all that is required is to simply excavate an appropriately sized trench, and rely on the natural capacity of the clay to collect the water and slowly allow it to dissipate into the ground. If you are fortunate enough to have that much-coveted Holy Grail amongst gardeners – freely draining soil – then your ditch will need to be lined to stop the water disappearing too quickly. Do remember, however, that unlike a pond, the ditch is supposed to be ‘leaky’, so you don’t need to line all of the hole – just perhaps the bottom third or so, possibly even adding a few holes to that let the last dregs finally flow away. A layer of pond compost on top of the liner will also help retain the water, as well as providing a medium for subsequent planting.

The design itself really depends on personal taste and your overall vision of the garden. A straight trench about 60cm (2ft) across and about the same again deep is perfect if you want to tip your hat to the traditional ditch, but within reason, they can be whatever shape or size you like – so if you’ve ever hankered after a faux-moat all of your own, here’s your chance!

Unique Planting Challenge

Once you’ve actually built your ditch, the next thing is, of course, to plant it – and this represents a quite unique challenge.

Unlike the clear planting zones you get in a pond that call for deepwater, floating, marginal and emergent vegetation, or the permanently wet roots but dry foliage of the bog garden, the conditions in your ditch will change considerably over the year, and often quite quickly. The plants you choose will face surroundings that can go from full of water to completely dry – and everything in between. It’s a lot to ask of any plant, but fortunately, there are plenty of hardy, and very attractive, species that can take that sort of thing in their stride.

Plants for ditches

When you’re shopping at the garden centre, the trick is to pay particular attention to the information labels; what you’re looking for are those pond plants which can be planted over a wide range of depths, from 0cm down to 15cm or more below the water’s surface.

A few ideal ones that you’ll often come across include:

Best plants for the Ditch bottom (most tolerant to prolonged submersion)

• Brooklime (Veronica beccabunga) with its attractive small blue flowers
• Creeping Jenny (Lysimachia nummularia) and its striking golden ‘Aurea’ variety
• Marsh Marigold (Caltha palustris) and the white form ‘Alba’
• Mare’s Tail (Hippuris vulgaris) – if only for its distinctive bottle brush foliage

Best plants for the Sides

• Yellow Button-weed (Cotula coronopifolia) named after its small yellow button-like flowers.
• Lesser Spearwort (Ranunculus flammula) – one of many from this family ideal for ditches.
• Ragged Robin (Lychnis flos-cuculi) for striking raggedy red flowers throughout the summer.
• Dwarf Pennywort (Hydrocotyle nova zealand) an attractive mound forming, spreading plant.

Best plants for the Top Edge(least tolerant to lengthy submersion)

• Chinese Marshflower (Mazus reptans) and the white ‘Alba’ variety
• Hostas; many attractive varieties – but watch out for slugs!
• Golden-Eyed Grass (Sisyrinchum brachypus) with distinctive yellow star- shaped flowers.
• Houttuynia cordata – for a great splash of ditch side colour.

A good planting scheme is vital to making the ditch a truly ornamental feature in the garden, rather than just a functional one, so it really is worth taking the time to plan exactly where each plant goes, and how it will fit into the final look you’re trying to achieve. As an added bonus for all of us gardeners who aren’t quite as patient as we’re supposed to be, most of these water plants tend to be quite quick-growing – so your new feature can look nicely established in a surprisingly short time.

So, there we have it; a low-cost, no-fuss, functional feature that looks good, can fit into just about any garden design and gives a respectful nod to tradition – it sounds about as British as all that rain………