Garden School:

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

Wednesday, 28 June 2017

How to manage your block paving drive

Do you have one of these block paving drives? Does it no longer look quite as beautiful as it used to when it was first laid?

Are there tiny weeds growing in the cracks? Moss? Nasty black lines where the joins go?

All these are signs that you need to do a bit of maintenance now, before things get out of control.

Why? Because even the best quality block paving is usually only laid on a hardcore and sand base, they are not cemented into place - the reason being that the individual blocks need to be able to move very slightly as cars drive over them, otherwise they would crack: and it also allows drainage of surface water. The edges may well be cemented in place, to stop them drifting apart - but not the main area.

You might think that a bit of mud or moss on the drive is not a problem, or that you don't really mind the odd weed or two: but the problem is that weeds tend to get bigger and bigger until the point where they start to force the blocks apart, leading to all sorts of problems. Also, any plant growth between the blocks will catch any wind-blown debris such as litter, or leaves, instead of letting them blow clean across and away. This material then rots down, creating more organic matter to feed the weeds.

Even a layer of moss along each join will catch water like a sponge, creating a nice planting environment for weeds.

So, what to do? Get yourself a long-handled wire brush, the sort that is sold for cleaning patios and drives. You can do this on your hands and knees, using a daisy grubber or an old kitchen knife, but a long-handled brush really saves the back...

Wait until we've had a few dry days, then start at one corner, facing outwards, and use a to-and-fro scrubbing motion along the join. Annoyingly, most of the best block paved drives are laid in a herringbone pattern, so each join is no more than one and a half blocks long.. so you don't get a chance to build up a good rhythm. Ah well, such is life. Scrub along the join. Take a small step to the left or right - scrub the next join. Take a small step... scrub the next join.. continue until you reach the end.

Change the brush to the other hand, take a half-step backwards, and scrub the join at right angles to the last one you did. Take a small step to the left. Scrub the join....

Continue doing this  until you are demented with boredom and can't take it any longer. Put down the scrubbing brush, go and get a normal yard broom or household (outdoor) broom, and sweep up all the loose bits. Then go back and scrub another section.

The reason for starting in a corner and looking outwards is so that you are not treading on all the loose bits, by they way: there's no point scrubbing them off, just to tread them all in again!

Here's one I did this week: the top (right-hand) half has been scrubbed but not swept, and I swept a small strip to make the difference more obvious: can you see where I've been?!

This was quite a large drive, so I did it in instalments over a couple of weeks.

When I'd finally finished, the result was spectacular, it looks just like new!

Having de-mossed and de-weeded it, the final job is to spray it with a residual type of weedkiller (Pathclear is the usual brand name, or something clearly marked "For paths and patios") to help prevent seeds from germinating and starting the cycle all over again.

So there you have it - how to keep your beautiful block paving drive looking like new: once a year, scrub it and sweep it!

Monday, 19 June 2017

Using Salt as a weedkiller

I came across this little oddity the other day: someone was seriously suggesting using salt as a weedkiller in the garden.

After screaming "Are you crazy??!!??" at the screen, I decided to do a little research to find out why anyone would suggest such a daft thing, and it transpires that it's part of the whole eco-warrior "we don't use chemicals" and "Monsanto [makers of Glyphosate] are the Devil" dippy hippy thing.

As you can tell, I'm not a fan of that type of thinking: it's fine when you only have yourself to think of, but if  you are growing food to feed the masses (who all want perfect produce, cheap), or if you are paid to produce a beautiful garden within strict time limits (in most cases, I'm only there for half a day a week), then sometimes chemicals - judiciously used - are the only answer.

So why do I shriek in horror at the suggestion of using salt as a weedkiller? Does it not work? Oh, it works all right: it works superly. It will kill any plant or gastropod within range: if you put salt on a slug or on the stem or leaf of a plant, the salt will allow all the water inside the body of the slug or plant to move outside, in a rather drastic manner. This is why slugs and snails "foam" if  you put salt on them: the salt draws out the water on the skin where it touches it, and the water inside the creature rushes outwards to fill the gap, gets drawn outside, so more water rushes out... so the creature dies, howwibly. *maniacal laughter in the background. Yes, I know they are all god's creatures, and that I am supposed to be kind and nice to everything, but news flash, a) I am not actually all that nice, and b) sometimes in life we have to make choices, and I would rather have undamaged greenery than have a huge population of gastropods. So there.*

This process is called Osmosis, and you can look it up for  yourself if you are interested: in layman's terms, the salt "pulls" the water out of the slug or plant.

The bad news is that salt stays in the soil for ages - not quite forever, but nearly.  Do you remember your bible lessons? The bad guys used to "sow the land of their enemies with salt". This means they would scatter salt on the farming land to kill all the crops, and to prevent any new crops being grown there for many years. The "enemies" would die of starvation, or would have to flee the area. It's not an allegory, it was how they actually did it.

So unless you want a garden in which the only things to grow are salt-hardy Oleandar, Rosemary and Butcher's Broom, you do not want to add salt to your soil.

This also goes for killing those slugs and snails, by the way - don't ever sprinkle salt on the ground, or on the critturs: pick them up (if you are squemish, wear latex gloves, or use tongs) and pop them into a jar or pot with some salt in the bottom. Every so often you can empty the shells out into the bin. Do not put them on the compost heap!

There's another reason for not sprinkling salt on the garden to kill slugs and snails: the eco warriors (or "eco worriers" as I think of them) say that it's very efficient, and unlike the blue slug pellets, does not leave any residual poison in the creatures, so they can be eaten by birds or vermin without ill effect. Not true! Just as too much salt in our diet is bad for us, highly salted gastropods are very, very bad for birds, and although I can't find any firm information on this one, I can't imagine that they'd be very good for moist-bodied frogs.

Although I would say that from time to time I empty out my salt pot onto the rough grass in front of my house, and within a night or two, the whole lot have invariably gone, shells and all: so presumably there is something with four legs that likes crunchy, lightly salted, snails.

As an even further aside, when doing the three-yearly re-blacking of the bottom of a narrowboat, I asked what we should do with the masses and masses of barnacles that we scraped off before we could get to the paint. "Oh, just leave them there, on the ground," said the marina's manager: "they'll be gone by morning."  And sure enough, they were, shells and all.

Anyway, back to the salt issue: even if you really, really don't want to use "chemicals",  what do you think table salt is, scotch mist? It's mostly sodium chloride, but if it comes from brine (ie "natural" sea salt, obtained by evaporating salty water such as sea water or salt lake water) then it will also contain greater or lesser amounts of magnesium chloride, magnesium sulfate, calcium sulfate, potassium chloride, magnesium bromide, and calcium carbonate.

If you choose to go for "table salt" then you should be aware that it has several additives: potassium iodide for one, to give us protection against thyroid disease: plus magnesium carbonate, calcium silicate, calcium phosphate, magnesium silicate, and calcium carbonate.These are added to prevent clumping, and to prevent it from absorbing water.

So it's not exactly "chemical-free", is it? And it's terribly bad for the soil, so just don't use it on the garden: either use the minimum amount of commercial weedkiller - which has been carefully tested, and calibrated to be effective - or just get out there with a daisy grubber and weed by hand or by hoe!

Saturday, 10 June 2017

How to move a rose - yes, it can be done!

Recently, a friend asked me about a problem she was having:  some mature roses were in the way of some unavoidable construction work. She asked if it was possible to move the roses, so that they could be replanted once the builders had gone.

The answer is "yes - probably!"

And by coincidence, I found myself doing exactly the same thing a couple of days ago, so I took some quick photos as I did it, on the basis that a picture is worth a thousand words, and it would save me quite a lot of typing if I could illustrate the job as we went.

Right: first job, cut down the top growth of the roses in question. Why? Firstly because any large transplanted shrub is going to struggle at first, so it is a kindness to remove some of the burden of foliage. Or, to put it another way, it will probably panic and drop a lot of its upper foliage anyway, on the grounds that all those leaves are just too much to support: so we might as well do the job for it. Secondly, for the comfort of the poor gardener who is being asked to dig it up: roses have thorns (technically, prickles, but I am not wearing my Botanist hat today, so we'll let that one go) which can make it extremely unpleasant to work close to them.

So, firstly, cut back a lot of the top growth. Aim to end up with something about knee height and yes, you are going to lose all those lovely flowers, so take them inside and put them in vases! Cut off enough of the outside "ring" of branches that you can get fairly close to the roots without being slashed to death.

Don't waste the bits you cut off, though: you can use them for cuttings. Look it up online if you're not sure, but it's basically choose pencil-thick sections, push five or so cuttings (each a good 8" long) around the edge of a pot of soil/compost, water them gently, let them get on with it for a year or so. Keep the pots watered, but not soaked.

Take a lot of cuttings from each rose: two pots of five cuttings I'd say, and don't forget to take photos of the roses and label the cuttings according to the photos. If they have name labels, so much the better, but if not, use your imagination: at the very least, identify what colour they are. This will be your back-up, in case moving the plants is not a success....

Here's what I was presented with: a climbing rose which had sadly lost its supporting tree, and was far too big to be allowed to regrow in this position.

Most of it had been cut off when the tree fell, but it had regrown a lot of whippy shoots -and a fair amount of weeds, as you can see!

In this case, my first job was to chop off the wildly long growth so I could get close enough to weed it.

 Here is phase two: weeds removed, growth cut back to something manageable.

Now we get the spade out, and cut vertically downwards in a circle around it.
 As soon as I started, I realised that there was one stout branch that was still too long: I'd retained it because it has three or more good strong shoots coming from it. But it was no good, it was in the way, so it had to go.

Here you can see me starting to dig in a circle around the plant.

Dig straight down with the spade, a full spade depth, or more if you can. Then start working across, under the rose: try to get as big and complete a rootball as you can.

Use loppers/secateurs to cut off roots as you meet them: you are not going to be able to get all the roots out, so it's better to cut them cleanly than to try to lever each plant out, ripping the roots as you go.

Having removed this one, normally you would carefully retain the root ball: but in this case there was a lot of couch grass running through it, so unfortunately I had to shake off all the soil in order to get the roots of the couch grass out.  This is sub-optimal, as it exposes the roots and damages the fine ones, but there's no point trying to replant something which is infested with a perennial weed!

Here is the plant in my bucket: please note that I  have brought along the labels as well -  it's always good to keep the labels with the plants!  In this case I only had the one to move, but if you have several different roses to move, then write out labels and tie them to the remains of each rose as you go.

As this one has  been cruelly stripped of the soil, I filled the bucket with water and left it to soak for 20 minutes or so - which also gave me the opportunity to check that all couch grass roots had been removed.

Then it was time to pot it up and water well.

It will now sit outside somewhere safe, until needed: the owner will keep it watered and, with luck, it  will survive.

If you are simply moving the roses, then obviously you don't need to pot them up, they can go straight to their new home which you will have prepared before digging them up: clear the ground where they are going to go, dig it over well, make sure you have removed any nasty perennial weeds such as bindweed/ground elder/couch grass etc: dig in some home compost or some well rotted manure in preparation and dig the hole ready, so that as soon as you lift the rose, you can trundle it straight over the the new place, and plant it. Water well, and keep an eye on them for the following few weeks, watering as necessary.

Although generally speaking, it is always best to have plants firmly in the ground, in some ways, it is not a  bad thing if you have to pot them up: it gives them the time to die, if they are going to die, before you expend the energy to replant them: and it's often easy to forget about a transplanted shrub, whereas if they are in pots, you will be more likely to keep an eye on them.

If you do have to pot them up, here are two Tips for watering: having radically pruned and root-pruned them, they will be a bit delicate for a while, so water them gently, don't drench them - get some drip-waterers, those gadgets which you fit onto an empty squash bottle, and which allow water to penetrate slowly and gently.

Second watering tip, get a squirty spray bottle, and when you've filled up the water bottles each day, "mist" the foliage with water. Don't feed them at this time, just let them re-establish their roots in the pots.

 If the potted ones fail, hopefully you'll have cuttings: if the cuttings fail, hopefully you'll have some of the potted ones: and if all else fails, well, time to buy new ones.

But it is well worth the effort to try and keep them.