the dutch touch

The rear view showing how uncomfortable it is.

What a wonderful sight.

WOULD I KEEP YOU IN THE DARK

This article is the nearest thing to a scientific paper that a retired painter and decorator is likely to write, once again Jack Gott triggered the idea. As you know both he and I are in awe of the Dutch growers. For centuries they've been in the forefront of horticulture. Considering they've had to reclaim land from the North Sea, and continue to maintain it, is nothing short of a miracle. For years all I thought the Dutch produced were windmills and clogs, but since getting enthralled in the world of dahlias, I realise they are the true professionals growers. For my part just to visit my Dutch friend Aad Verwer's site, proves to me they are in charge, unfortunately, with the expansion of the European market they are having to cope with ever decreasing prices, I suppose it will settle down in the end, but for now it is a bit of a headache.

Before I decided to write this article, Jack and I had a slight difference of opinion regards a little thing called breeders rights, you see the Verwer brothers breed many dahlia varieties for the European market, and so obviously they want to protect their special varieties by applying a sort of patient on extraordinary varieties, there are not a great many from their vast collection that have this honour bestowed on them, one of my favourites though is Art Nouveau. The reason the company does it, is to stop other nurseries profiting from their endeavours. I'm dead keen on breeders rights, I think if a breeder raises a cracking variety, they should be able to profit from it, not Tom Dick or Harry. It's a bit like the record industry, if an artist writes, or makes a song popular, why shouldn't they be the ones to make the profit. It's different for us amateurs, we haven't had to earn a living in horticulture, mores the pity. It isn't as if the Verwer's don't pay for the privilege, it costs thousands of pounds, or the Dutch equivalent to set this process up, and it doesn't stop there, every so often they have to send these varieties to a laboratory to be checked. To see whether they are the same pure strain that they started with, and of course this entails more expense. I've had the variety Art Nouveau for a number of years now, I have maintained it, and propagated it, filled my garden with it, and I only paid for the variety once, when I bought it out of a British catalogue, that came through my letter box. If you would like to acquire some of these beautiful varieties you only have to leave this site via the link http://www.verwer-dahlias.nl/ to see for yourself one of the top nurseries in the Netherlands.

Ivor Mace a Champion Exhibition Chrysanthemum grower told me a couple of years ago, to get a pure strain of many of his giants chrysanthemums had cost him a Kings ransom. I was enquiring to see if I could get breeders rights for Charlie Dimmock, come on now, the dahlia of course, but it worked out far to costly. I was going to ask if the charity Break Through Breast Cancer wanted to place breeders rights on the variety, but thought better of it, as it would probably have taken forever to regain the cost. I'm not finished with this breeders rights business though, just as soon as we've had this years elections, I shall write to whoever's in charge, and demand scrapping the cost of breeders rights for charity varieties. Who am I kidding, but it's worth a try.

Now back to the plot, breeders rights wasn't all Jack and I talked about, when it come to Dutch growers. He'd been over to see his contact you see, they'd given him a grand tour, he'd had the run of the place, one of the partners, or brothers was a sort of laboratory type person, it's all scientific over there. I think the skills are handed down within the families. Most of the growers know each other, and many of them have connections in the same markets, the thing that intrigued me was, how they produced their tubers, I asked my friend Aad once, what ratio of the three essential elements did they use to produce the enormous amount of tubers, bit cheeky really I suppose, but I needn't have worried, I didn't get an answer, some questions should not be asked, not when it's a fellow's livelihood. Needless to say I am still experimenting in the tuber business, I'll get there in the end, all I know is, to finish them off you need plenty of potash.

In conjunction with the growing of the tuber, is the growing of the plant, I thought like the British grower, they would have huge glass houses, don't you believe it, for the most part the tubers that produce cuttings are all grown in the dark, they use large windowless barns. It's more like a place that you'd grow mushrooms, all the tubers are nose to tail with their brothers, batches of each variety are tuber thick on raised heated beds, Jack's boys have a double tiered system, in order to utilise the heat.

That's when it hit me, what if I set up an experiment, to see if this system worked for me, of course I couldn't do it on a grand scale, but then I wouldn't have to. I told Jack, and I think he was a bit bemused, but he humoured me, I could tell, even though I've never met the guy. That evening I sent off for some more heating cable, you know the type we use with a thermostat, for our propagating area. I set about making the place I was going to use for the experiment suitable. I was lucky because the space I had in mind was ready built, all it needed was a large hanging door to keep the heat in, and the light out. Below is a rough sketch of what I was trying to achieve, the only difference in the drawing, and the real thing was, the curtain was replaced by this hanging hinged door.





		Ken's Mini Dutch Barn.			The two hot boxes.

The sketch also shows the two tiered system, with a couple of large trays to hold the tubers, that was the idea, but as time was running out for the experiment, I abandoned the idea, and reverted to placing seed trays of `chicken legs' directly on to the washed grit, that covered the heating cables. I wasn't going to tell you, but having ordered a twenty foot cable, I found out to my dismay, that it was exactly half of what I needed, that's the worst of being a retired painter and decorator, of course it meant another week was lost, waiting for the longer cable to arrive. Mind you it gave me time to realise, having two drawers that big would be far to heavy to manage, as each would hold eight seed trays, and a number of half pots. Any way far from wasting the first twenty foot heating cable, I used it to increase my propagating area in the glass house, I asked Jack if I could run two lots of heating cables with the one thermostat, and he insured me all would be well, as long as I put the wires in the right terminals, he's an electrician you see. Below are a few photographs of Ken's Mini Barn in action.





	Bottom tier.				Top tier.




	Closer.				Close up.

	Darkroom, or pencil cuttings.				The last three rows are darkroom cuttings after three days.

You can see the whitish shoots emerging from the tubers, the amazing thing to me was, not one of these cuttings were hollow, not one, even the thickest of them had solid stems. Once they're inserted they green up in three days, obviously soaking up the light, and rapidly making chlorophyll, isn't nature grand. I'm convinced the cuttings were made up of root cells, as they had been produced completely in the dark, think of the space you can save with this method. Of course when you insert the cuttings the base remains white, and the theory behind it is this, they should root far quicker than a conventional cutting. Best of it was, I didn't once use a knife on them, consequently I didn't have to sterilize anything, I just broke the cutting off at compost level, it was just as Jack had told me, it couldn't have been simpler, I'm not sure how long they would stand this treatment, but I'm sure they'd produce until you had enough cuttings. Jack said his boys snap them off, and insert them in large trays, and they go in a poly tunnel on top of more heating cables. They are left there for no more than three weeks, when they go in to other poly tunnels with no heat at all, talk about grow them the hard way. As Jack says we're to soft with them. I'm practically certain they are not potted on, but are planted directly from the trays they were rooted in, or should I say, knocked out of the trays they were rooted in, and planted from their torture bus. Here are a few photographs to give you some idea of the work involved.







		Get these done by five o'clock and you can go home.			Here's Ton hanging around again.




	Aad Verwer in between Karma Amanda and Karma Lagoon.				Across the frames towards the glass houses.



	This variety is planted for the cut flower trade.		As is this splendid variety.


	I should imagine this variety is for garden display.		Like wise this dark leaved variety.

As you can see there is a lot to do before you have the finished product be it flowers or tubers, and of course we mustn't forget those varieties that are grown for the cut flower trade. Groups of special cut flower varieties are kept separate, and continually cropped. You can't go without taking a butchers at a few photographs off the Verwer Brother's Web Site, they are some of my favourites.

Summing up, I have found in most cases the dark room cuttings have roots coming from every side of the cutting, unlike conventional cuttings. It is not a one off experience but every cutting from the hot box produced the same kind of roots, so a big plus for the Dutch method. However on the down side a good cutting grown in the old way, roots quicker, I thought it would be the other way round, being the material we are using was produced in the dark, and the plant probably thinks it was underground, and thus makes root cells, evident in the number of roots that are produced. The rooted cutting also has a totally different appearance, I call it the `Date palm look' because they are inserted almost pencil like, and as soon as they make roots, the growth at the top of the pencil springs to life. I've added a few photographs to illustrate this.

The best varieties to use in the hot box are strong growers, such as Taratahi Ruby, Charlie Dimmock and the like. Next time you see a variety hanging in a apartment store in a plastic bag, check it out, look at how many tubers it has grown by the traditional Dutch method, because you can bet your bottom dollar it was produced in Holland or at least by the same method. I've just realised I must mark each pot tuber for comparison when I do my final assessment.

For my final paragraph, and the summing up of what I've called the Dutch method, I must report the contents of an email I received from Aad Verwer. He pointed out not all Dutchmen use this system, and explained although some did, most growers who are concerned with the health of their dahlia stock use the more conventional methods that involve the use of light and glass. In other words they use greenhouses as we do, It appears no control of virus stock can be seen when you grow propagating material in the dark. Fair enough, but should you know the stock you have is free from disease, I'm convinced this method is another alternative to increase your stock. I can imagine in America, and Canada where they have basements this system would work a treat, of course you would have to root the varieties in natural light, or at least accompany the dark room, with a similar room with `Grow lights' As long as your stock was tested from time to time all would be well. What's that, how do you know if a certain variety has a virus? Let you in to a secret, but don't tell Stan Hall I told you, it's a bit rustic but it works. When you're taking your dahlia cuttings, sow a pinch of annual flowering tobacco plant. When your dahlias are growing well, take off a single leaf from a variety you suspect could be carrying a virus, after crushing it rub the juices on to one of your tobacco plants, if it starts to yellow and die after a week or so, you most likely have a virus in the plant you took the leaf from. It is probably tobacco virus, another reason to finish with the dreaded weed. You see there are a number of dahlias that carry viruses, but unfortunately don't show any signs of infection, bit like humans, who are carriers, but never develop the full blown symptoms. The reason I know this is, two years ago I grew a new variety of Nicotiana (tobacco plant) called `Apple Blossom' It was a dwarf, and was ideal for inter-planting with an Ageratum I was using called `Blue Blazer' in a bedding scheme in the front garden. All started well, the plants germinated well, the dahlias were racing away, when just before the tobacco plants came in to flower, one by one they died, by the autumn I found the culprit, it was some bad stock of Wooton Cupid, outwardly the variety was growing in the normal way, but I read this particular variety can carry virus without much outward appearance. How did I know for sure the stock was bad? Because there was a batch of Nicotiana that were growing perfectly okay in the back garden, out of the reach of these offending Cupid's, but how did the dahlia transfer the disease to the tobacco plants that died? Probably aphids or earwigs, both have the ability to eat and move on, and my spraying routine wasn't as exacting then. In the case of the surviving Nicotiana plants, my guess is they were to far away from the offending dahlias, and of course lady luck played her part, having read about Wooton Cupid's trick with viruses in the same years as the mysterious death of two boxes of Nicotiana's, I crushed a leaf of Wooton Cupid and smeared it on to one of my remaining tobacco plants, within three weeks most of the bed showed identical symptoms as the first batch, and eventually died. Fortunately it was then late October, but a lesson had been learnt, from a wily old gardener called Stan Hall, and a book I hired from the Library.

Hope you enjoyed the Dutch experiment. Ken Stock.

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