Garden School:


Garden School:
Teaching this week: Rose pruning (as always!) and water management

Friday, 28 February 2014

Salix Caprea Kilmarnock: How Not To!

Under the general heading of "Crimes against Horticulture", this little tree makes me cringe every time I see it:

Why?

Let me count the ways...

It's worth repeating that these are not "natural" trees, but are two types in one. The top part is a strongly weeping Salix Caprea, (Goat Willow, also known as Pussy Willow) grafted onto a straight upright stem of another willow. 

It's a very popular little tree, being in effect a dwarf weeping willow on a short, upright stem.

But they need some very particular maintenance: you have to cut out any growth from below the graft or join, as it will be from the rootstock, ie not weeping at all.

As you can see here, the groundsman has totally failed to nip off new rootstock sprouts as they occurred, and now they are bigger than the original tree.

So that is the first and biggest mistake.

Then there is the terrible "pudding bowl" chop that he's done to the top part. Wrong! Wrong! The effect to aim for is a "light, airy waterfall" of foliage. Chopping off the ends like this ruins the shape of it, it looks ridiculous, and it will take quite some time to get it back in shape, as every cut end will now sprout a handful of new shoots.

I'm not even going to mention the "why bother with it" staking style, nor the tasteful ruff of weeds at the base...

So what should you do?

Firstly, regular vigilance to remove any shoots from low down on the stem. If you see the first sign of a bud, rub it off. If you don't spot it until it's a small shoot, that's ok, just get the secateurs and cut it off, flush with the stem. If they are springing from below the ground, gently scrape away the soil until you see the point where it comes from the stem, and chop it off there. Replace the soil. If you just cut it at above-the-soil level, it will sprout several new stems, hydra-like, and you will have half a dozen instead of one.

Secondly, instead of chopping the top,  thin it out by removing a few selected branches, right back to the centre. This reduces congestion, and retains the shape.

If you have one that is a dense mass, get down on hands and knees and work your way under the umbrella of foliage to the central trunk. Reach upwards, and start by cutting out all the dead stuff you can see - this is a good time to do it, early spring, as the live shoots will be budding, making it easy to spot the dead ones. It's also easy in summer, but with all the leaves on it, it can be a bit harder to see what you are doing. Either way, get out all the dead stuff and see what you are left with. If it still looks dense and top-heavy, go back underneath and take out some of the lowest branches, as close to the main trunk as you can.

Oh, and from the outside, take out any branches that are not weeping - anything flying off in all directions (happy and partying, as it were, rather than weeping) is probably a shoot from the rootstock, and needs to be removed otherwise it will take over from the weeping branches. And considering that you bought it for the weeping branches, this would be a waste!

If some of your remaining branches are just too long, and are reaching the ground, then take hold of one at a time, work your way back up it to a point about a yard above the ground, and find the nearest small twig that is arching upwards and outwards, rather than inwards. Cut the branch just below this twig.

This retains the weeping outline, and reduces the chance of new growth pinging off in the wrong direction.

Having done all this work, sit back and enjoy it, and make a note to repeat the process once every year or so.

As an aside, the tree will never get any "higher" than it is: the height is dictated by the height of the graft. So although the stem will thicken, and the weeping growth will get longer and thicker, the overall tree won't get any higher. Well, not more than a couple of inches higher. This is why they are so popular - they really do stay small, and are ideal for front gardens, or for the smaller garden.

Now, all I need to do is decide whether I should do a Guerilla Gardening raid on this industrial estate, and sort out this poor little thing!

UPDATE: Yes, I did: check out Salix caprea: Guerilla Gardening for the full story!

Thursday, 13 February 2014

Bamboo - how to thin out an overgrown clump

Bamboo is a fabulous plant, but even a favourite specimen can get out of control.

There's a simple solution to this problem - in fact there are two! You can either dig out sections all the way round the base of the plant, thus reducing its size (and providing some handy offsets for planting elsewhere, or for potting up and selling/swapping) - or you can just prune it.

Here's one I did earlier: my Client thought it was crowding out the Mahonia, and flopping too far over to the right:


So I crawled underneath on my hands and knees, armed with my new lilac secateurs (more of them next time), to have a good hack at it.

My principle in these cases is to push a hand in through and across the clump, to separate out a slice in the desired direction: in this case, I wanted to reduce the front, so I divided out a good 6" slice, and bent them gently downwards to see what the effect would be.

As it looked about right, I then simply cut all of those stalks off, as close to the ground as I could.

I then did the same for each side, but the back didn't need attention. Here's the result:

Much better!

The overhanging fronds no longer brush onto the Mahonia, we can clearly see the trunk of the Elm on the left, and although it's not as clear from this angle, the bamboo is now clear of the pleached hedge as well.

The Client was very happy, not least because you can now see the stalks of the remaining fronds.

This was somewhat accidental - as they had been at the "inside" of the clump, they had very few stem leaves, and I suspect that by mid-summer, those bare stems will be well-clothed.

I'm not a great fan of stripping off the lower branches of bamboo, as is frequently recommended these days, in gardening magazines: I prefer them to be decently clad, but this is quite a  nice compromise.

To give you an idea how much I chopped off, here is the wheelbarrow afterwards:

So if you are troubled with an overlarge bamboo, that's all you have to do.

One word of caution - if you think that your bamboo is not just too thick, but too tall as well, then whatever  you do, don't just chop the tops off.

It looks terrible. Worse, those chopped tops will sprout little "lollipops" of foliage, which then looks ridiculous.

Just do this, as described above: and once you have reduce the size of the clump, reach in amongst what is left and cut out about a third of the stems.

Stand back and admire it - it should be much airier, and thinner.

Still too tall? Find the tallest stems, trace them back to ground level one at a time, and chop them off.

There you go! Thinner, airier, less tall, and still stylish.

Here's one I did last year:

Before I attacked it, it flopped right out over onto the lawn, smothering the lavender and generally looking completely out of  control.

Alas, I took this photo before I had finished raking out the huge piles of dead bamboo leaves, so it still looks quite messy, but once the bed was back to clear earth, it looked really stylish.

The Client was very pleased, and took back her comments about "death to all bamboos". Which was nice.

Tuesday, 11 February 2014

Recycling Part 3: wheelie bins.

Earlier this year, I went on a trip to learn what happens to our garden waste, and what happens to our kitchen food waste.  My third recycling visit was to find out what happens to what we put in our "Recyclable" wheelie bin.

This meant a trip to Milton Keynes, which is where the rubbish goes to be sorted.

Yes, I know it's ridiculous to send truck after truck from Oxford to Milton Keynes, but it costs a huge amount of money to build these enormous recycling centres, and it really is cheaper to pay the fuel for the lorries to truck it around the country, than to build more of the centres.

The intake is very much what you expect to see - a huge mountain of mostly plastic rubbish:

I know people always say this, in this situation, but I have NEVER seen such a huge pile of waste.

The lorries unload it at the open bay doors, and it gets shovelled forward by tractor-type vehicles, into those slots you can see on the left.

At the front of each slot is a conveyor belt, carrying the stuff upwards into the plant.

To give you an idea of scale, the blue bits are full-sized bin bags, and that wall would be way above my head.

The first level of sorting occurs automatically - strong magnets remove metal, then lighter material ie plastic, and cans, are split from the heavier stuff, glass is sorted from the paper, and so on.

As you would expect, the inside of the building is a monumental jumble of conveyor belts and noisy machinery.

Our tour guide (it was so noisy that I never did catch his name) told us that this facility had been built inside an existing warehouse, which was more or less square. If they had been building from scratch, they would have built a long thin shape, which would have made processing easier.

But as it is, they have had to fit the machinery in to the space they had, hence the apparent confusion and the multiple levels of conveyors.

This machine was captivating -  when we arrived, it was inactive, and seemed to contain just a steep row of gigantic metal teeth.

When it started, the noise was enough to make most of us jump!

I'm standing on tip-toe looking down into it (probably breaking any number of health and safety rules)  to see what it's doing - it's "jiggling" at high speed, which causes the lighter items - plastic bottles  - to rise to the top, while the slightly heavier cans are spat out the bottom.


Much to our horror, the next thing we saw on our way round the site was a human!

Yes, we expected it all to be machinery and conveyor belts, but almost at once we went through this sorting area, which deals with items that don't fall into the initial sorting categories.

They are mostly non-recyclables like food,that have been wrongly binned, and which have to be pulled out by hand.

Yes, she's wearing thick gloves, but it's still a disgusting job, and this area was pretty smelly. All the instructions from our various councils clearly state that the recycling bin is not for organic matter, but some idiots always think they know better - or perhaps they just don't realise?

Talking of which, I wonder if you, like me, have been a bit careless with washing out glass and tins before binning them? I used to rationalise it by saying that glass and tins would be melted down, so it didn't really matter if I rinsed them out before binning them, or not.

But it does matter, for two reasons: one is that the people who work in the recycling plant don't deserve to have to work in a stink. The second is the obvious one - RODENTS!

Oddly enough, the workers don't mind rats, or birds - they consider them to be just wildlife, and quite interesting to watch, which is a refreshing point of view. But the problem is that the locals complain about it to the council, who then have to come round and inspect, and insist that poison is put down, which means they have dead rats and birds to deal with, instead of live ones.

So please, wash out your tins and cans before you bin them! You don't have to waste hot water on them, just put them to the side of the sink and rinse them in the used washing-up water before you tip it out.

So, back to the tour: after gaping open-mouthed at the seething mass of conveyors and sorting machines - including a really clever high-speed plastic sorter, which appeared to work by magic - we went round to the hand sorting areas.

Here we found the classic idea of recycling - long conveyors, lots of women standing to each side,  watching the flow with eagle eyes and pouncing on the contents, dropping them into various chutes.

I assume that they take it in turn to be at the first position (lots to choose from) the middle positions (a bit humdrum, perhaps) and the last position ("It's all up to you!").

It was far too noisy for them to talk, and when we left the area I asked the tour guide what the level of staff turnover was.

"Practically nil," he replied "we've had the same individuals working here for eight years."

When I expressed surprise, he told me that although the job itself might be fairly unpleasant, they had a very good social life.  Every single one of the sorting employees were Polish - I had earlier spotted that every noticeboard had duplicate notices in Polish, so I had guessed that there would be a lot of them, but I had no idea it would be 100%. Or that they would stay so long! - and working there meant that they were inducted and instructed in their own language, while being given the chance to learn English, and to settle into a nice English suburb.

Finally we were at the end of all the conveyors, and watched the plastics output crawling continuously off the line, as workers chopped it into pallet-sized bits, tied it up, and sent it out to the yard, not failing to hand-pick out any odd bits of non-plastic that they saw.

Apparently this material goes off by boat to China for processing.

Again, the natural response is to ask why it can't be processed here, and again the answer is money.

China will accept bales of plastics which are something like 95% pure plastic.

The UK plants will only accept 100% pure plastic.

It would cost a lot of money to ensure the level of intensive sorting that would be required to remove every particle of contaminant.

So it's more cost-efficient to get a slightly lower price for the product, and to ship it to China, than to improve the sorting procedures to hit the 100% level.

It was most amusing to hear the waste constantly being referred to as their "product", but of course it is - the plant does its best to raise enough money from selling the various sorted products to cover the cost of running the plant.

And this is in all our interests - otherwise we will have to pay more in Council Tax.

So what lessons did I learn from this outing?

Rinse out your cans and tins.

Don't squash one type of rubbish into another - don't fill boxes with plastic then put the whole thing in the bin.

Don't leave lids on bottles or jars.

Don't tie up like-for-like rubbish: someone has to manually cut your string and then put it in the landfill pile. Just pile it into your wheelie bin.

So there you are - I now know what happens to all my rubbish, where it goes, and how it is processed!

Thursday, 6 February 2014

Trellis for roses/climbers: Best Way

I keep having this conversation with different Clients, so it's clearly worth repeating: if you are thinking of growing roses or other climbers up a trellis, here are a couple of points to consider before you put up the trellis.

Firstly, don't clamp the trellis to the wall: plants need air circulation to help them to grow healthily, and a lot of mildew problems can be avoided if you put wooden blocks onto the wall first, then attach the trellis, so that it is at least an inch or two clear of the wall.

This also allows space for the stems to twine around it: this applies mostly to jasmine and honeysuckle, as personally, for roses, I never twine the stems around the support - instead, I always tie them to the support. I don't like seeing contorted rose stems, I would rather have them growing straight, so that I can more easily select the ones I want for my "framework of old wood" that we all strive for (along with "open goblet shaped" shrubs).

Here's a photo of a really good example:

As you can see, the Client here has attached study cross-struts to the walls, making them part of the overall design, then has simply screwed the panels to the cross-struts.

Five minutes with a screwdriver, and we can get the whole lot off for wall repainting, although in fact there is such a good gap that last time, the builder just ran his long-handled roller along behind it from each side!

The ultra-efficient way is to use hinges at the bottom of the trellis panels, with a swivelling peg or clamp at the top. Then, when you want to repaint the wall, you can unclip the top, and gently lean the trellis outwards, either to the ground, or to a whatever angle you need, instead of having to cut everything down to nothing. 

Simple, eh?

Sunday, 2 February 2014

Ferns: Time to cut them back.

It's been such a mild winter that many of the ferns around the garden are still looking quite lush, but eventually there comes a point where the old fronds start to go brown, and look bedraggled.

It is also nearly the point where the new shoots will start to unfurl, and it's important to clear away the old shoots without damaging the new ones, so I've been doing Fern surgery all week.

Here's one I did earlier:

This is what it looked like - very typical of the normal garden fern, one of the Dryopteris family: the long fronds are flopping over, and going brown at the base.

In this case, it is also being swamped by Lamium or deadnettle, which is grown here for groundcover, as it is a steep bank.

I'm not keen on letting the lower storey planting swamp the ferns, as they tend to root themselves within the fern: so this annual clear out is a good chance to pull back the Lamium and give the poor fern a bit of a breathing space!

All you do it get the secateurs, and carefully clip back each frond, as far back to the base as you can.

This is what it looks like afterwards: a bit bare and brown, but you can just about see that the new fronds are starting to swell.

In this particular case, I also cleared a space all around the fern, uprooting the Lamium, removing any other weeds, and generally giving the fern a bit of elbow room.

It won't be long now before the new fronds start to uncurl!