Garden School:


Garden School:
Teaching this week: Right tool for the right job: how to grub out unwanted shrubs with a pickaxe...

Sunday, 21 April 2019

Box hedges: how to do a drastic recut

OK not really that drastic, not compared to some that I've done *laughs*, but here's a nice small-scale example of how to tame a Box hedge that has is getting away from you.

The hedge here goes "round the corner", so that from the outside you can't really see that there's a gate there at all, for security.

However, visitors were starting to complain that they couldn't get the gate open, especially when the hedge was wet!

The hedge has been trimmed regularly, but this demonstrates the sneaky nature of clipped hedges: unless you are really strict with them, they will gradually grow further and further out, until they take over the entire path. Yew does it, Box does it, Lonicera nitida does it (really quickly!) and the answer is always the same - every couple of years you have to be brave, and speak severely to them. Just running the hedgetrimmers over them is not enough, as most hedgetrimmers will only get through the softest, most recent growth.

This was the problem with this small hedge: the owner has a dinky little battery-powered hedgetrimmer which is simply not man enough for the job. (Another reason why I prefer to use hand shears.)

So, what do we do?


Here's what we started with: you can just see the gatepost, buried in the corner of the untrimmed hedge.

As you can see, the bit on the outside is growing a long way beyond the gate post, and furthermore it has been allowed to grow top-heavy, giving the impression that it is leaning outwards.

This is bad horticulturally: hedges should always slope the other way, getting narrower at the top, not the bottom.

This allows light to fall on the whole side of the hedge, so that all of it will grow and thrive.

By letting it loom like this one, the lower part of the hedge gets little light, and grows only very slowly, while the top section grows ever more vigorously, so the problem just gets worse and worse over time.


So, step one: chop into the over-grown section.

You can use string, or a cane, to get a straight line if you need to, or you can just do it by eye.

To cut those thicker stems, you'll need secateurs, and occasionally loppers. Cut them one at a time, and try to keep a fairly straight line if you can - but don't worry too much at this stage.

This shows the first cut about half-way done.



Here we are five minutes later, the outer edge of the hedge is now upright again, and there are three bucketfulls of cuttings in the green bin now.

(Don't compost them, they don't rot) (well, everything rots if you leave it long enough, but don't bother adding them to your normal compost pens!)

As you can see, the very bottom of the hedge is still narrower than the top, because it had been overshadowed for quite some time.

But it should grow back now, now that the light can get to it.


Here's the same thing from the side-on angle, to show how what appears to be a solid hedge is actually a framework of bare brown branches, with an outer layer of green leaves.

This is absolutely typical.  Most dense hedging looks like this, if you gently part the outer leaves: and if garden owners don't realise this, it can give them a nasty shock when they see a newly cut-back hedge!

Luckily, Box, Yew and Nitida all share a wonderful feature, in that they will "green up" if you do this to them - unlike the unlovely Leylandii hedges, which are famous for staying brown and hideous forever, if you cut them too far back.

No, these classic hedging plants will leaf up in a few weeks, which is why they are so popular for hedging.

To finish this job, I gave the rest of the hedge the usual spring clipping, to level it and neaten it: then I carefully cleared up all the mess, shaking the hedge to get all the loose bits off, and cleaning out underneath it as well.

It then receives some feed - growmore, or liquid seaweed feed - and a good watering, to give it a head start: and in no time at all, it will be green and lush again.

If you want to see what this process looks like on a bigger scale, I spent three years getting a Nitida hedge into shape, here is the article about it.

So there you have it, how to get a hedge under control - and now the visitors won't get wet hands when they open the gate!


Thursday, 4 April 2019

Willow - still time to coppice it

Yes, it's that time of year again: last chance to coppice or pollard your domestic willows, before they start growing again.

What's the difference, between pollarding and coppicing? Only a matter of height, that's all. Coppicing is generally done at ankle height, where you chop all the stems off right down low, all at the same time. This causes the plant to throw up a whole heap of nice clean new shoots, all at the same time, so they grow all together, long, thin and straight.

Perfect if you want to grow your own fencing, weaving, or burning material, as long as you have sufficient number of plants to do them on a 7-year cycle, ie cutting just one section of them each year (a different section, of course).

Pollarding is exactly the same thing but higher: these days, we mostly see it done on street trees, the ones that are savagely cut back by the council every year or two, until they are just a trunk with a bunch of knobbles on the top. That's pollarding, and it's done to keep them down to a manageable size.

Back in the day, it was done for a different reason - to prevent the new shoots from being eaten by livestock. Trees would be pollarded at one height if there were cattle in the area: somewhat higher if there were horses, with their longer necks.

In one of "my" gardens I have two rather different pollarding jobs: both on willow trees, but very different in appearance.

The first one is a medium sized multi-stemmed tree (left), next to the lake, which gets so big that it obscures the view, so every second or third year I pollard it.

Here it is in the "before" state, and you can see that the end of each trunk has a fan or bunch of branches all sprouting from the same place - this shows where I have pollarded it in previous years.


Here's a close-up of what it looks like part-way through the job: you can see that there are stems of various sizes, some are spindly little pencil-thick things from last year, some are as thick as a thumb, they'll be two years old, and the fattest ones will be three years old.

It didn't get done last year, so it's been three years.

As you can see, all I do is snip/cut/lop/saw off every single twig or stem, as close as i can to the main trunk.

It can get a bit tricky to reach all the way round: please note the watery background, which tells you that this willow is half in, half out of the water. In order to reach the branches growing out over the water, I have to shin up the trunk, cling like a monkey and lean as far as I dare.

When my bravery runs out, I go and get one of my long-handled tools and do the rest from the bank: it's not quite as "good" as doing them by hand, as it's not possible to see what you are cutting, but willow does not seem to mind...

And this is the finished job, please note the long-handled saw leaning casually against the trunk.

To give you an idea of scale, it's 8' long.

And you can see here, just how much of it leans over the water!


The other willow, the far side of the lake, is quite different: it's a small one, just a little bit more than head height, and in summer, it forms one attachment point for the lakeside hammock, so it is vitally important to keep it in good condition!

This means that I pollard it every year, to keep it small and sturdy.

It may be a lot smaller, but the treatment is exactly the same: secateurs in hand, I snip  off as many of the branches as I can reach, using a lopper for the bigger ones.

I then wriggle round the back of it to snip off the rest, taking great care not to fall in the lake.





 Here's the finished article: you can see how strange and lumpy it looks, but that's what happens when you pollard regularly.

And no, that's not a missed twig sticking out the top - it's a completely different tree, way, way in the background!