I’ve always been a big fan of urban hedges. I reckoned that – like trees – they must help manage water runoff and moderate temperatures. Planting relatively large numbers of mixed native plants together in cities had to be good for wildlife too – maybe even more so than trees because of their diversity, volume and value as a wildlife corridor and resource. I had supposed – partly because of that – hedges in cities would also be good for human mental health.
It turns out that they have much more significant and direct benefits.
We have thought for a while that trees can reduce particulates from, for example, car exhaust. The plants either absorb them through their stomates or catch them on their leaves, to be washed off or fall to earth in the autumn. Earlier studies suggested that well positioned trees could reduce particulates by up to a quarter.
It makes sense that hedges should be pretty good at this too. They’re not only denser but also at a better level to intercept exhaust fumes. A recent study supports earlier findings supporting this. Although its efficacy varies according to conditions, a roadside hedge can reduce near road air pollution by up to over 60% in some cases (including the cancer causing pollutant black carbon). Remarkably, hedging is not only much more effective than trees, but also seems to be more effective on its own than in combination with trees.
We have a massive problem with air pollution in our cities. The UK has regularly breached legal standards in London. Many thousands are dying from the consequences, and heart breaking individual stories are emerging. A recent WHO report found that over 4 in 10 primary school pupils in the UK are breathing dangerous traffic generated particulates.
The government seems short on practicable ideas to tackle the issue, at least in the short term. Why not plant hedges?
We recently planted this specially selected triple width mixed native hedge at a school in Yorkshire. It will be a dense filter (and impenetrable barrier!) soon enough, running over 100m along the school’s boundary.
Planting hedges in cities is simple and cheap, and they are demonstrably effective at reducing harmful pollution. Mixed native hedges like you would find in the country are attractive too, with lots of wildlife value. What’s not to like?
The commercial world of native hedge plants is a funny one. There are a few hardy folk out there selling British hedge species which they themselves have grown. Things like Hawthorn and Blackthorn. As you can imagine, it’s not an obvious way to make a million. There’s quite lot of time and manual intervention involved and – like last summer – you’re dependent on the weather to a degree, even if you can afford glass (greenhouses) and water.
Worse, it’s quite difficult to persuade people to pay a lot for them. They look around and ask why they couldn’t just liberate the odd sapling, or at worst grow plants from seed. Some do.
Worse still, it’s much easier to grow them abroad. Most of the “native British” hedge plants planted here are in fact imports from Denmark, Holland, Italy… Our few remaining “forest nurseries” are mostly small and struggle to match the economies of scale of their continental competitors.
British Hedge Plants To Be More… British?
Fortunately there is light at the end of the tunnel for them. We’re beginning to be more picky about where we source our plant material. For good reason. Plants grown here from UK seed are going to be more helpful in UK ecosystems. They’re going to be better genetically equipped for life here. They also reduce biosecurity risk. Regulation is never going to be as effective at reducing the risk of imported plant disease as… not importing plants. Increased controls on imports may be part of horticultural life in post Brexit Britain.
We’re at an interesting moment of inflection, and seeing a change which will accelerate. And not just because of potential political changes.
It was a terrible growing season here because of the Beast from the East, which meant plants were knocked back, followed by the dry summer. Many plants which should have been saleable as “60-90cm” grade are only 40-60cm. Some plants aren’t saleable at all. There’s an acute shortage of stock.
This effect has been worsened by higher demand. That’s partly because people are choosing to use plants grown here – I think possibly in the wake of the Ash dieback fiasco. Landscape architects are asking for British grown plants for their projects – and there is some large infrastructure work about at the moment. Individuals are planting more hedges too.
So bear with us if we are struggling to find exactly the hedge plant you want. It’s actually a sign of exciting change.
Hedgelaying now seems hopelessly quaint. It’s incredible to think that there would have been thousands of agricultural workers spending months and months painstakingly managing hedges with slashers and axes. The time it took is mind boggling. This sweet video from 1942 would have been completely unremarkable – I guess the landgirl would have seemed the most unusual thing about it!
Each area had its own style; in the video it’s Midland, with “binders” to support the cut stems, or “pleachers”, while they regrow. The local tradition where we live is much more rustic but clearly identifiable, as a Dorset hedge. Its development is easy to explain; it only needed to be proof against the lowland sheep which were such a familiar part of Hardy’s landscape.
I have to say I love pretty much everything about hedgelaying. I learnt how to lay (or “layer”) hedges on a weekend course many years ago. It’s something you have to do if you would like to pick it up. The Conservation Volunteers produce an excellent practical handbook, too. My skill levels are pretty basic (!) – I don’t lay 100s of metres of hedge every year to practice and I don’t have an expert watching over me – but Dorset hedges are pretty simple.
Why do I like it so much? To start with there’s the connection with that rich rural tradition. Like planting local apple trees. It’s genuinely interesting and demanding work too. Even with a chainsaw (not available in 1940s Northamptonshire!) it’s taxing and rewarding labour. Last off it makes a much better hedge.
In the days before barbed wire, hedges had to be stock proof – that was kind of the point. This photo shows another section of Hawthorn hedge I planted a few years ago. Stockproof it clearly isn’t. Lambs etc could cheerfully wander through it. Left unmanaged and you have a series of small trees, which is what many of the common hedge species (like Hawthorn and Blackthorn) want to be.*
This couldn’t matter a row of beans in terms of our hedges – a barbed wire fence protects the garden from rampaging cows. It does matter for other reasons though. Hedgelaying makes for a much thicker, denser hedge with a really solid base. You can see that these young hawthorns, planted around 50cm apart in a standard staggered double row, already look as if they will form a much wider barrier because of the brash I’ve left on them and the way their stems are lying. Even in its current state it provides a much denser – if much reduced – barrier. It will whistle up in no time, incidentally.
We’re pretty exposed, so the new hedge will provide a more robust and more substantial windbreak. More than that, though, it will be excellent for wildlife. That’s not surprising. Enormous numbers of invertebrates feed on common native hedge plants. In Hawthorn’s case it’s apparently 149. Its early blossom is a boon for pollinators too, and its berries in autumn for small mammals and birds. These species in turn bring exciting predators. Some insects lay their eggs on hedge plants to overwinter. Pollinators like bees, moths and butterflies enjoy not just spring blossom but also summer flowering hedgerow shrubs like roses and honeysuckle. Managing these plants through laying and then trimming them, rather than flailing, keeps those resources intact.
Hedges can provide fabulous shelter and safe corridors for movement – “wildways”. Their value for this is enhanced considerably if they’re laid and allowed to breath a little. We’re lucky enough to have dormice running around in our mature hedges, and shrews and voles use hedgerows as permanent habitats. Toads and other amphibia and reptiles find their dense, damp cover helpful. Birds are attracted by the insects, berries and nuts that a dense hedge provides, but also benefit from the protection of larger, denser hedges. They’re a great substitute for the wood pasture or woodland edge habitat that’s so rich in biodiversity.
Anyway, I’ll keep you posted on the progress of our little hedge. It’s always slightly unnerving to see this kind of reduction but it’s something I won’t have to do again for up to a decade, and won’t take long to look mightily impressive. It’s only about 30m long, but should be a lovely and important addition to the garden. Here’s one I did a few years ago – pictures at the end of the blog.
*In modern times flailing the bottom and surrounds of hedges and using herbicide around them exaggerates this tendency. You end up with a series of plants which look like forks; a single stem supporting a few prongs. Not really a hedge at all. Eventually the forks give up the ghost completely.
Max Hooper has just died. He was a proper botanist, who became known because of his work on British hedges in the 60s. From the obituaries and his writing he seems to have been quite a character too.
Like many I came across him because of “Hooper’s Rule”. This was his rule of thumb – for obvious reasons not definitive – for dating hedgerows. Walk along a 30 metre length of hedge and count the species in it. Multiply that number by 100 and you have a reasonable estimate for the age of the hedge.
There was also his work on the extent of the hedge loss in the UK. Hooper uncovered it by looking at RAF reconnaissance photos. 50 years ago we were losing over 10,000 miles a year. 10,000 miles! I didn’t think we had that many hedges – and how could we continue to be so casual about them?
I was staggered by Hooper’s Rule too. I started looking much more carefully at the hedges around our house in Somerset. All around us were early medieval hedges. Given the history of the village this was entirely predictable, I suppose, but I was amazed. Amazed that I hadn’t stopped twice to think about these important ancient things. Amazed that their diversity and history went unnoticed, at best. I then realised the hay meadow next door was probably pre 15th century. It was suddenly obvious to me that we didn’t even begin to appreciate or understand what was underneath our noses.
Realizing this and the extent of the destruction to our environment still going on was an important part of my decision to leave the City. There were much more important things to do. I started a business promoting – among things – native British hedge plants. Thank you for helping to convert me, Dr. Hooper.
By my reckoning, this bare root planting season the Habitat Aid hedge elves will have planted something over 130,000 plants around the country. There’s some repairing of existing hedges but it’s mostly new planting – woodland areas and new hedges, often on the sites of old grubbed out hedgerows. This makes me happy, particularly as they’re all species native to Britain and plants grown from British stock by British growers. Great for the wildlife that depends on them, great for everybody. So long as they’re looked after (!?) in a modest way we will have left our mark on the landscape for many years.
This season hasn’t been without its troubles, however. Most folk use bare root hedge plants; they’re cheap, easy to handle, and have a good success rate. They’re planted when dormant, in ground that’s not frozen or waterlogged. Here are the two problems. First off, as the more observant of you might have noticed, some early blossom has already been out for a while and the first shimmers of green are apparent in the hedgerows. It looks more like mid-March than early February out there. This means that there’s a huge rush on to get plants in the ground before they break dormancy, in which case they react badly to being transplanted. Alternatively, if like us you have suppliers who can chill their stock, you can hold spring back.
We’ve needed to do this for a number of sites which are underwater. In my book it’s probably not terribly bright building a solar park on the Levels, in a site surrounded on all sides by rhynes (deep drainage ditches) and where the local botany consists exclusively of rushes and sedges. I’m surprised the arrays haven’t started to sink. Anyway, the chances of planting that particular site before April are zero.
Climate change is having an effect on how we’re planting these hedges and what they’ll look like. Sections of Hawthorn and Hazel will fail because they will rot in standing water. We’ll replace them with Willow and Dogwood. The hedge will look much redder in the winter and spring. We are slightly moving old hedgelines in order to avoid really wet areas and tweaking mixes for some sites, particularly in the wetter west, to include more water tolerant species. The look of the countryside will change.
The methodology of planting will alter too. Specifiers – typically in our case ecologists and landscape architects – will have to be more flexible when it comes to planting times and species. A site can’t be planted between November and end March if it’s typically submerged for that period. More hedge mixes need to include wet loving plants; without them there can be some real disasters as “extreme” weather creates impossible conditions for some species.
There’s never a really good time of year to flail a hedge, but it’s particularly galling to see so much hedge cutting going on at this time of year.
It could be why the prodigious bounty of our native hedgerows tends to be over-looked, despite the fad for foraging. Sloes, hips, haws, elderberries and blackberries have all been excised from the hedges around us, which have been neatly cut as they are every year. It’s a real pain; armed with a variety of recipes we always look forward to raiding nature’s larder at this time of year.
In the past folk used to collect apples, berries and nuts from hedges as a free supplement to their diet, but for many birds and mammals this food source is rather more critical, of course. And flailing hedges like this doesn’t just impact on larger animals. It’s not surprising the Brown Hairstreak is such a rare butterfly; it lays its eggs on young Blackthorn plants. There’s no chance of them surviving an annual flailing; populations will be wiped out in a single year.
That’s not quite true – best practice is to lay a hedge, although that’s a time consuming manual business and is often not a practical answer. I’m a sucker for hedgelaying though, and lay all the hedges we have around our patch in Somerset. Follow the link to find out why.
We forget why and how to plant a native British hedge. We take them for granted. They’ve got a history going back to the bronze age, making them one of the oldest man made features in the British landscape. Native plants make a good, fast growing privacy hedge which is recommended for security. They’re also beautiful things and a fantastic resource for wildlife and foragers. Mixed hedges using native species are easy to recreate and manage, and I’m always surprised that more folk don’t go for them.
Why a Native Hedge?
Our native hedge plants seem to me to be a bizarrely under-utilized resource in urban environments in particular. Perhaps people associate them with unruly mixed hedges, when they want a clean and tidy look. In which case, why not suggest a clipped single species? These plants can be as architectural as yew or box; use Hawthorn, for example. Like Blackthorn, a great security barrier but beautiful in spring, and fruitful in autumn.
For summer colour, completing all year round interest, punctuate with our native Honeysuckle, Lonicera periclymenum, or Dog rose,Rosa canina. To my mind, though, the more species in a hedge the better, if for no other reason than increasing its associated biodiversity. Structurally mixed hedges look sounder to me as well; you need a good mix of suckering species like Blackthorn and Hazel to continue to give it a good thick base.
This means a traditional hedge is excellent for security. If native hedges have kept cows and sheep out for hundreds of years, they’ll deal with people too! Hawthorn and Blackthorn – the clues are in their names – make impenetrable barriers. Hawthorn’s synonym – “Quickthorn” – also tells you how fast it will grow
Native hedge plants make good visual screens too. Beech and Hornbeam keep their leaves in hedges, and additionally to Yew, Holly and Privet are also evergreen.
As with all our native plants, common hedge species have unique relationships with our native fauna. When they think about the food that they provide most people think about the berries for birds and small mammals – and larger mammals like gardeners! There’s a largely unnoticed community of animals further down the food chain, however, which depends on a hedge for other forms of sustenance.
Our butterflies and moths have unique relationships with our native plants, many of which you can include in a hedge. The Yellow Brimstone, for example, lays its eggs on Buckthorn, on which its caterpillars feed exclusively. Brown Hairstreak has a similar relationship with Blackthorn.
Think of the number of plants in a native hedge and you can imagine the volume of pollen and nectar even a short length will produce, as opposed to individual plants. The mix of species also ensures a long flowering period – there’s rarely a time when something isn’t in bloom. Hereabouts it’s the Blackthorn blossom in early spring which saves the honey bees from starving, and at the end of the season the ivy in autumn lets them stock up for winter on warm autumn days. Different flowers attract different pollinators, so a mixed native hedge will support a whole range of them.
Plants like blackthorn and hawthorn provide fantastic shelter for invertebrates, small mammals and birds. Hedges are handy corridors for wildlife too, and offer relative safety for animals while they move about. One of the issues exercising the conservation lobby at the moment is the fragmented nature of biodiversity hotspots, which need to be joined up. Hedges can be a pretty good way to do it, at least on a small scale. Animals don’t just use them as “wildways”, but also as navigation features. Bats use them to find their way across the landscape, for example, and bumblebees fly by them too.
Starting a Hedge
It couldn’t be easier to start a native hedge – after all, these are our British plants, so it should be easy to grow them! Before you start, prepare the ground by weeding or spraying off a strip about a metre wide. If you have livestock, thin about whether it would be best to wire the hedgeline before or after you plant your new whips. Don’t under-estimate the width your hedge will grow to.
Find a good quality supplier of British plants. There are plenty online, but do look carefully – please source your plants from a British nursery. Some of the large scale hedge renovation over the last 20 years has used plants from all over Eastern and Western Europe. There are lots of reasons to use hedge plants with British provenance. Some suppliers are either coy about provenance or infer it, so ask.
You’ll need 5 plants per linear metre to create a stockproof staggered double thickness hedge. We usually recommend 50cm between rows. That’s not to say your hedge must look like that. You might not have enough room for two rows of plants, for example, although the thicker the hedge the better from the point of view of wildlife. Some folk want a really thick, triple thickness hedge (7 plants a metre). If you wanted something optimal for a “wildway” you could plant rows up to 1m apart.
Most woodland nurseries sell a “conservation hedge mix”, which is a good diverse default mix for the agnostic and will qualify for grants. It’s suitable for a wide range of situations and soils and consists of species widespread across the UK. If there are species in it you don’t want or species you particularly do, the nursery will usually happily tweak it for you. We don’t suggest using Blackthorn in a hedge next to a lawn, for example, because it suckers freely. On the other hand, you do want some suckering species, like dogwood and hazel, to help thicken up the hedge. Alternatively you might want a more formal single species look – a hawthorn hedge looks good, for example.
Most farmers buy the smallest size plant on offer, which is often 40-60cm. Personally I’d stretch to the next one up, say 60-90cm, which is the size we used in the picture. They’re still pretty small whips, which are easily planted and quick to establish. There is no point buying anything bigger as you’ll end up with a hedge with no bottom.
The whips will be bare root as they’re much easier to transport and will take much better than pot grown. They’re consequently delivered from November while they are dormant. They should arrive in special packaging, so will sit in the shed/garage quite happily for several days. If you’re not planting them for a longer period, heel them in somewhere.
When you do get around to planting your whips the key thing is to keep the wind drying their roots out. I march around with the whips in a bucket of water. The other big issue is frost; don’t try sticking them into frozen ground. They’re easy to plant, particularly if you have a two person planting team. One of you needs to open a slit in the ground with a spade and the other just pops a whip in and treads around it. If you have rabbits or deer you will also need the ubiquitous plastic spiral and cane. These will also help support and generally protect the young hedge plants. The wretched things aren’t biodegradable, however, so if you can fence in your hedge instead that’s a better option.
First off, you MUST keep the base of your native hedge clear of weeds. The whips don’t need to compete with perennial weeds while they are getting established. If you don’t use a mulch then you’ll have to weed or spray for a couple of years.
Once established – after a couple of years – removed hedge guards and canes if you have used them.
Without plant management, in a few years’ time you’ll have a different problem to deal with. Although we’ve pretty much arrested the decline in the length of hedges in the UK, they’re beginning to turn into rows of small trees. Left unattended your native hedge will go vertical, which is less helpful for all than a dense hedge with a wide base. You can start this process by pruning the growing tip off your new whips and encouraging lateral growth.
As time goes on the ideal way to ensure a perfect hedge is to lay it, but that’s often not practical. That’s a whole different blog anyway! Establish a trimming regime that impacts the least on local wildlife. The Single Payment scheme asks for hedge cutting to stop between 1st March and 31st July, but the optimum time to do it is January and February. That’s after the berries have been eaten but before birds start nesting.
Don’t butcher a hedge to an inch of its life, as you often see flails do, and trim it in a two or three year rotation to let it fill out. The Single Payment scheme quite sensibly specifies a 2m wide uncultivated zone from the middle of the hedge.
If you do need to take extreme action to get a mature hedge back under control, coppice it in sections, year by year, to minimize the impact on wildlife. Ideally, gap up a hedge while renovating it with locally sourced whips in keeping with the species you see around you.
We saw the stage show “Enron” a couple of weeks ago. Great entertainment, but it also brought back memories of my time in financial services, as I spent over twenty years working in the Japanese stock market and well remember a couple of periods of grotesque excess. I met and worked with some able and lovely people from those years (he says hastily – you know who you are!), but like any business I also bumped into some who were… not. One of the morals of Enron is something I’ve always felt about the City – you can’t regulate greed. If you nurture a system of reward which encourages people to take excessive risk with either their employer’s or their clients’ capital you can’t simultaneously ask them to behave nicely, let alone ethically. After a while they won’t understand what “ethical” actually means anyway, which adds to the ever increasing cost of regulation. In any case, how do you regulate a global industry, as folk like the oily Bob Diamond are forever pointing out.
I digress. What’s this got to do with nature conservation and botanists? In order to make our children want to become botanists rather than bond traders I am beginning to think we have to effect a much more fundamental change than any kind of regulation or funding can achieve. Whatever you might make of the current spending cuts, it’s for sure that government will shrink over the next decade. There will be a smaller stick and less carrot available to promote the environment generally. What is a tremendous short term problem for many of us could be a great opportunity though; I don’t believe regulation and artificial incentives are the way to preserve our landscape long term any more than prison is for criminals or the FSA is for banks.
There’s an old bugger in our village who just ignores any form of planning control. The local council has given up trying to get him to comply to all sorts of requirements. His yard is a rubbish strewn shambles, his outbuildings are semi-derelict, his land is a mess. He’s behaved this way for at least 40 years and he just doesn’t understand why people think he’s being anti-social. If he did, of course, he probably wouldn’t do it; I think underneath it all he might actually be a nice bloke. Of course we need regulation as a back stop to deal with this kind of thing as we do prison for hard core offenders, but it doesn’t work on its own.
For a start, nature is too complicated. Legislation protecting hedgerows in the UK has resulted in folk no longer ripping them out, but rather destroying them through benign neglect. A hedge can quickly become a line of shrubs, which becomes a line of isolated shrubs, which disappears. When does a hedge stop being a hedge? Artificial incentives are just as difficult. Correct me if I’m wrong, but my understanding is that there has been a very low take up of the more complicated and consequently more beneficial seed mixes for field margins. Why? Because farmers are paid for the initial establishment of the margins and not their upkeep. Without (expensive) maintenance, which they’re understandably unable to carry out, a wildflower rich margin will just revert to grass. In any case, why are we paying to try to compensate for the farming methods we have ourselves demanded as consumers?
Is the answer to all of this education rather than funding? The dampness of the squib that is IYB2010 (gentle reader, you can admit you have no clue what IYB2010 is) goes to show that biodiversity is just not part of the mainstream yet in the same way that alternative energy and energy conservation are becoming. Our children need sensible role models to reinforce the message, rather than the City traders who rags like the Sunday Times still lionise, and – forget government and government funding – we ALL need to better understand and value these folk and what they do.
Amazingly we are still losing our hedgerows, according to a report from the Campaign for Rural England (CPRE). “Amazingly” because I thought they were so well protected by legislation and because people understand how important they are, both historically and environmentally. The CPRE report restates the case again for hedgerows, and calls for more specific regulation and continuing funding to protect them. All power to them.
Forget their environmental value for a moment; like meadows, many hedges are ancient monuments. In Devon nearly a quarter of hedges are over 800 years old, and some are based on Bronze Age banks. They should enjoy the equivalent of Grade 1 listed building status. Unlike the period 1950 to 1975, when many were ripped out, the more recent problem has been neglect. According to the report, from 1998-2007 the km of “trees/shrubs/relict hedge (and fence)” has increased while the km of hedge has decreased by 6.1%. This is an important distinction. Unmanaged hedges turn into lines of trees and shrubs, which have less and less value and eventually disappear. Alternatively, single lines of plants are often mercilessly flailed, and end up looking like stumpy toothbrushes. These are no more hedges than the X Factor is opera.
We’ve restored the hedges here, which had become very X Factor. My educated guess is that they date back to the Middle Ages, but they had recently suffered from being choked with dead elms and having been left to grow out. Their ditches were filled up and sheep and cows had wandered through them. We’ve cleared the ditches and laid most of them over the last few years, replanting the gaps with a British grown and appropriate mix of native hedgerow plants. Hedge laying is not only a brilliant way of creating a lovely thick hedge, with all the attendant benefits that brings, but it’s genuinely good fun to learn and can be a great art. One of the charities we support is the National Hedgelayers’ Association, which might seem an esoteric choice, but it reflects our reckoning of the importance of hedges in our landscape.
You wouldn’t believe the difference it has made. Newly laid hedges look like they’ll take years to recover, especially given the local style is pretty aggressive, but we now have the most beautiful thick hedges. I cut them carefully by hand too, which means the boon to wildlife is tremendous and that us humans get to see everything in flower. As the report points out, managed hedgerows are very important habitats for a variety of birds and mammals in particular, and even I – no great twitcher – can see the difference in the volume and species of birds we now have.
Still recovering from our older son George’s 18th I spent some down time in the garden today looking for butterflies. Appropriately enough, as next week is Butterfly Conservation’s Big Butterfly Count, sponsored by Marks and Spencer. I counted 6 species in half an hour loitering around the herb garden – Common Blue, Large White, Gatekeeper, Meadow Brown, Small Copper, and Brimstone. Nothing unusual to get the hardened Lep excited, but really good news for me; when we moved here there were only Whites around, so we’ve done our bit to create good habitat for butterflies. I’ve also recently seen Six Spot Burnets and Large Skippers. In a very modest sort of way I feel like a kind of God; there’s a lot you can do to build up a good population of colonial species like these.
In the herb garden Oregano seemed to be a particular magnet for the Browns, and in the borders Veronicastrum for the Brimstones.These guys are a particular success, as I hadn’t seen one around here at all until now. Why have they suddenly arrived? Because I planted a short stretch of Alder Buckthorn, their larval food plant, in a section of hedge. You can see how tasty it has proved. With butterflies it’s not just the nectar plants you need – it’s their whole habitat. When you get that right the effects are pretty much instantaneous.