Garden School:


Garden School:
Teaching this week: Rose pruning (as always!) and leaf mold.

Tuesday, 20 December 2011

Fremontodendron...

..."What's one of them?" I hear you ask.

No, you probably all already knew about this shrub, but for some reason I have never encountered it before last week.

Well, I know the reason why - it's  not a fully hardy shrub, and as such I would not expect to find it in any of my gardens, where phrases like "value for money" and "doesn't require faffing"  are frequently aired.

But I haven't even seen it in garden centres, and I do like to wander round the plant sections... I can't imagine how I'd missed it.

Anyway, I was recently out walking around Buckland, which is a village just north of the A420 - pretty, but somewhat blighted by the noise of the road, and having to always plan your journeys so that you don't have to risk death by turning right out of the village across the A420......

...and on the front of one of the cottages, right on the road, I was intrigued by an espaliered shrub that I simply didn't recognise.  It had tiny, pretty, leaves, not so much oak-shaped as shaped like those of Hydrangea quercifolia: very downy underneath, and it was still flowering, even in December!

Here is the main body of the plant... and yes, it's a south-facing wall, but it's right onto the road, no sheltering garden or wall, just the main stem going straight down into the tarmac. Heaven knows where it finds water and nourishment!


And here is one of the flowers:



Aren't they lovely?

If you google for it and look at images, you can see that in a good year, it is completely smothered with these large, saucer-shaped yellow flowers, and it's an absolute picture!

As I said, I didn't recognise it, so I took a leaf home and identified it.

And then, just one week later, I was working for the second time in a new garden that I have take on over the winter, and blow me, there was another one! Freeform this time, rather than espaliered, and again, grown against a south-facing wall but not in a particularly sheltered position, and again, not into good garden soil, but right on the edge of a concrete path.

So beware, clients, I am going to be singing the praises of this plant, and will be trying to find sheltered nooks for it...

Monday, 19 December 2011

Prairie Planting - easy autumns!

As I haven't said anything much about Prairie Planting recently, I thought I'd better explain why: it's because all through Sept, Oct, Nov and Dec they don't require any work.

Well, barely any work, apart from raking through the Stipa tenuissima as they flower, to avoid soggy brown masses after any rain. Oh, and maybe a little bit of weeding.

But so far, I haven't even cut down the very dead Echinacea purpurea or coneflower. They are now matt black, still standing stiffly to attention, and actually looking rather lovely, if not particularly colourful. I have removed one or two stems that have collapsed sideways, only because they look so untidy, but otherwise I have left them standing.

Likewise the Cardoons or Cynara cardunculus, which are holding up wonderfully this year.  Last year the seed pods opened quite early, and they shed masses of fluffy seeds all over the garden. Luckily most of them failed to germinate, otherwise it would be standing room only for Cardoons! This year, however, the heads are intact, and they weren't as big as last year - a mere 5' tall (errr, not even 2m tall) whereas last year they were towering over my head.

So, here are my Prairie beds this week: a Picture in Shades of Beige?


 The other one looks better, with the sun behind me:


That's more like it, a Picture in Shades of Gold.  Glorious, aren't they? Not to everyone's taste, and it's not possible to achieve the look without a large garden, but they certainly are very low-maintenance at this time of year.

Now I have to wait and see how long I can leave them before I start the winter clear-out.

What does that mean, exactly?

Well, I am sure you have all read in the books about "leaving your perennials to make a fabulous frost display".

This phrase is usually accompanied by a beautiful photo like this one (right) showing an atmospherically back-lit image of the perfection of crystallised foliage, shimmering in the winter sun.

And have you ever tried leaving your perennials unchopped in autumn?

In the UK, we are usually treated to howling winds and rain through November and December, leaving us with something more like this:

Yes, that's more familiar, isn't it? Ruined plants, blackened foliage, and as soon as the frost melts, it collapses into a soggy mess which then solidifies into an impenetrable crust, preventing the warm soft rains of Spring (er hem) penetrating the ground.

Or, more realistically, preventing the bulbs around the perennials from coming up cleanly, leaving each one with a lid of sodden black muck on it, spoiling the blooms.

And at the very least, making a safe haven for slugs and snails over the winter.

Oh dear, do I sound a bit negative about the frost effect? (said she, unrepentantly.)

Well, in a word, "yes",  I am very negative about the frost effect. I don't know which country contains the people who rhapsodise about it, but it can't be the UK.

Over here, we generally get rain before we get much in the way of frost, and that does rather tend to ruin the foliage, flatten the stalks, and destroy any symmetry of form.

Every year I am requested to leave plants unchopped "for the frost", and every year, a few weeks later, I am asked to clear up the horrible black soggy mess...

...but this year, so far, it has been surprising dry, and the wind has done surprisingly little damage, so for the time being I am leaving the Prairie beds as they are.

Wednesday, 14 December 2011

Vine pruning

Aha, we're back to Wisteria pruning again!

No, today it's Vines, but it's very much the same thing as for Wisteria: at this time of year, it's time to cut back all the new growth, right back to the basic framework of knobbly spurs.

And, once again, I forgot to take photos until I was half-way through the job, sorry!

With vines, my first step is always to cut and gently pull away all the entangled new growth of the season - at this point, I am concerned with getting the bulk of the unwanted growth out of the way, so I just cut roughly a good 20cms or 8" away from the main framework

So here is the "Before" of one end of a vine in my charge, at that stage:

Often, due to the tendrils, it takes some careful snipping to release the unwanted growth, and I often have to snip out long growth in sections, particularly when it has sneaked around behind the supporting wires and has headed skywards, unseen behind the covering leaves.

As you can see, it's had all that work done, and is now reduced to the basic framework with untidy sprouts in all directions.

The next stage is to cut all of those right back to the framework, leaving maybe one or two buds on each one. Don't forget those sloping cuts, again!

Once this is done - right - you should be left with some gnarled old branches, ending in knobbly lumpy bits.

This is correct pruning for a vine!

I know it looks drastic, but honestly, you really have to do this every year.

Normally, presented with what you can see in this photo, you would say that one stem of growth should have been allowed to remain, on the far right-hand of the upper framework.

The intention would be to train this stem along the wire to the right, allowing it to become part of the framework.

However, in this case, the client has brought in a new vine this year, which we are going to train up next year to take the place of this one, which has never performed well. The new vine is to the right of this one, and is going to move left along that wire, taking up the empty space next season.

I am hoping that by the end of the next season, I will be able to dig out this one altogether.

And yes, if it were my garden, I would have taken this one out altogether as soon as the new one was delivered, but I was instructed to leave it for one more year, "just in case".

Oh, one other job to do at this time: gently remove any loose bark from the main old framework.

I know it seems terribly harsh, you do think that the stems would benefit from the loose "skin" as frost protection, but - and you can look this up for yourselves on google if you don't believe me - the books all say that we should remove loose bark as it harbours pests, particularly scale insects, over the winter.

So, gently rub off any loose flaking bark, and rub off any scale insects that you should happen to see, as well.

"What's a Scale insect?" I hear you say.  Oh, have you not met these strange little things? They are kind of primitive-looking things:  basically sap-suckers with hard outer shells which they clamp down tightly against the bark, to prevent birds getting at them.  Like all sap-suckers, they rarely kill plants, but they weaken them, which reduces their vigour and makes them more prone to diseases, and other pests. For this reason, you should try to reduce their numbers if you can; and removing the dead bark and rubbing off any that you find is a good start.

What do they look like? Just google "scale insect" and click on "images". They are tiny, semi-hemispheres, brownish or orangish in colour, and it helps to imagine them as tiny barnacles, clamped onto the stems of vines and many other plants. How small is "tiny"? Oh, er, about a quarter the size of a fingernail, how's that for precision? (Hey, I'm a botanist, not an entomologist!) At this time of year they are quite dry, and often you can just sweep them off with a finger.

So there you go, quick guide to the Winter Tidy-Up for vines, hope you enjoyed it!

Tuesday, 13 December 2011

Wisteria pruning, ready for winter

I covered this topic a while ago, but I hadn't taken photos:  we all know that phrase "a picture is worth a thousand words" and I should imagine there were some readers who were wishing that I had chosen photos rather than thousands of words on the subject!

So when I was asked to tidy up a Wisteria last week, I thought of you brave souls, ploughing through my thousands of words in the hopes of a) learning something or b) being mildly entertained, and I managed to pull out my phone and take a photo.

Here is what you might call "before":


Well, technically, "half done" as you might notice that on the right-hand side, there are clear signs that I have already been at work - yes, I was well into the job before I remembered that I had intended to take photos...

Anyway, generally speaking, this is the "before" picture: the Wisteria in question has had at least two runs of summer pruning, clipping off all those monstrous whippy green shoots that make the place look so untidy, and is still lightly covered with leaves, although they fall off at the slightest touch.

Summer pruning, as mentioned in the earlier entry, is not just to remove the wild growth and retrieve your gutters, it is also to promote the formation of flowering buds, rather than endless whippy growth.

Winter pruning is for neatness, and to ensure the flowers can be seen to their best advantage. It is also the time to assess the shape of the plant, and to make decisions about how you are going to manage it in the forthcoming year.

So, armed with secateurs, small steps, and my trusty long-reach pruning pole, I set to work.

The first job is always to sweep off as many loose leaves as you can reach: I use the pruning pole or a rake, and gently wipe it across as much of the plant as I can reach. That takes care of most of the loose leaves. If they don't come off easily, then it's too early! Leave it another couple of weeks and try again.

I always start at the bottom, which may seem wrong, but it means that it's easier for the debris to fall straight through the stems to the ground.

So, ground level: wipe off the leaves, gently tug off any stubborn stalks, then cut back all the newest, palest gray stems to just one or two buds. Don't forget to always make a clean, sloping cut, sloping away from the bud so that the rain, snow, dew etc slide off the stem. If any of the knobbly spurs are getting very congested, now is the time to thin them out.

Next stage: get up on the steps and do everything you can reach, then it's out with the long pole and repeat the process up to the top - although, as mentioned in the earlier post, it's not possible to be surgically precise with your sloping cuts when you can't even see what you are cutting....

Oh, at this point I should say that my professional insurance only covers me for working up to 1.5m off the ground, so I have to work on a set of low steps, or with a long-reach pole. You may prefer to lean a ladder against the wall and simply climb up and down it.

I would say, however, that I encourage all my "Senior" clients to make the decision to get a long-reach pole and lower the height of the Wisteria to the point where it can be managed from the ground, rather than risking life and limb clambering up ladders. Many of my clients are at that stage where they are looking to simplify their gardens, and reducing the height of a climber that requires regular pruning is quite a simple thing to do.

I know it sounds like a cowardly thing to suggest - but it has the huge advantage of bringing that aspect of their garden back under their control, rather than struggling to do it themselves, or having to pay a man with a ladder to come round and do it. And after all, what's the point of Wisteria blossom so high up that you can't see them clearly?

Anyway, once this is done, stand back and look at what you have left.

This is time to decide if it is becoming un-balanced, if one part is too thick, perhaps: or you might decide that you are sick and tired of brushing past a mass of wet leaves every time you walk up the path, or tired of being poked as you walk underneath an archway.

If any of these apply, get out your loppers, or pruning saw if necessary, and remove any branches that you no longer want.

In this case, the client and I agreed that it was getting too "proud" at ground level: that is, it was projecting out into the courtyard too far, and becoming a nuisance.  So we cut off all of the branches that were poking out at head height or lower, leaving all the sideways-growing ones.

When you have completed this phase, stand back again, and take another look: once you are happy with it, you can sweep up the mess, and there you go:


It has a sort of elegance of simplicity, doesn't it? And I assure you that I have been doing this to this particular Wisteria for over eight years now, and if flowers wonderfully every year.

In this particular case, it doesn't go much above the top of the picture, as the building is a low-eaved thatched cottage, and in earlier years we had a lot of problems with the whippy growth getting caught up in the thatch.

Now that we keep it to this height, it is much more manageable, which has proved to be a big relief to the client. Sometimes, in my job, it's important to give priority to the wants of the client, rather than the wants of the plant.

Monday, 5 December 2011

Caryopteris: time to prune

Caryopteris x clandonensis - normally just a smallish shrub, with pretty, foamy blue flowers all through late summer into autumn.

They haven't had the best of years this year, but then we've had some very odd weather...

Anyway, it's time to prune them ready for the winter, for two reasons: firstly because the flowers are better on new wood than on old wood, and secondly to prevent damage over the winter.

Here is one that I prune every year - left to their own devices they grow in a rather bush-like shape, something like Spirea, but this one was planted rather too near the front of the bed, and the client won't let me widen the bed, so I have had to encourage the Caryopteris to form a woody framework which is going up and along, rather than out, with the new growth falling in pendant fashion from the framework.

It makes a very attractive shape, and is rather more interesting that yet another fluffy round ball.

Here it is "before" - a rather tangled mess, looking quite bedraggled as the flowers have all finished and dried off to brown fluff. Normally with anything grown as a pendant, such as willow-leaved pear, that miniature weeping willow Salix caprea 'Kilmarnock' and so on, the aim is for a "light airy waterfall".

Hmmm.

More of a flourishing hydro-electric plant, in this case.

As you can see, it completely obliterates the front of the border: this fits in perfectly with the tall scented shrubs running along the back of the border, and through the summer it creates a wall of colour and scent. Lovely!


Right - on with the pruning.  It's a simple process: go over each branch, and cut back all the new growth to stubs on the old wood.

Rather like Wisteria, or Buddleia: you keep the old framework, unless it has split, or is growing in the wrong direction, or getting a bit top-heavy.  In this one's case, I always take off a few of the bigger branches that are coming forward over the grass, and I try to keep it looking fairly balanced.

Once all the long twigs are gone, we are left with a much neater and much woodier-looking shrub:

Suddenly we can see through it to the shape of the shrubs behind - you can now see the Abelia in all it's end-of-season fluffy seed-head glory. That one had a major chop two years ago, and this year only needed the over-long new growth removed, which I did about a month ago.

Further behind you can see where I brutally chopped the other shrubs two years ago, forcing them to produce strong thickets of upright stems from much lower down.

And of course you can now see the Hellebore thicket!

Here it is from slightly closer, so that you can see the stubs - very similar to the method used for encouraging fruiting spurs in Wisteria, or in vines, or for that matter in fruit trees.


And once again, I have to say how impressed I am with professional plant photographers, as all of these photos do rather look like a mass of greenery..... but I hope you can make out enough detail to make sense.

I also have, in another garden, much smaller examples of this shrub, pruned in exactly the same way but only 45cms off the ground (she said, proudly and metrically - although I am thinking 18" of course) rather than 1.5 metres - I'll  try and remember to take a photo of them next week, to show you the comparison.

So off you go, get out there and prune!