Winter Protection

After the devastation of the last few winters, it is essential that bonsai enthusiasts in the UK take precautionary steps to protect their trees from the harsh winter that will be coming. It may snow in October and we are likely to see some very low temperatures. Lots of factors are causing climate change, man made and natural, however what is certain is that if we have another harsh winter and trees are unprotected then we will have a lot of dead trees on our hands. I will admit that over the last two years I have lost close to £10,000 worth of trees. I cannot let that happen again. This happened because I didn't prepare for both the weather and my absence from the country during it.

Having learnt my lesson the hard way it seems perverse to me that many people are unwilling to invest a little time, effort and money in creating winter protection when they may have spent lots of it on their trees. Bonsai is a continual investment, if that is lost at any point, then all the previous work and effort has been wasted. Just for the want of a little extra spending, everything goes to waste. The same is true for soil, pots, fertiliser etc.

Bonsai are more susceptible to the cold as the roots in a pot will freeze much easier than those in the ground. The earth retains a lot of heat and only the surface layers of soil are seriously affected by the frost. In a pot, the entire root ball can freeze and cause fatal damage to the tree. This must be avoided....but how?

Trees must be protected from cold soil temperatures, over watering, and wind. To this end, for the few trees I own, I have constructed a small poly tunnel, in which there is a heating bed to maintain soil temperature above freezing, a fan heater to keep the air above freezing and hopefully settling on the tunnel itself. All delicate trees will be buried within the heating bed which contains a heating element attached to a thermostat which will activate the heating once the soil temperature drops below 3 degrees C. The idea is not to keep the trees growing but rather to stop any damage. The lack of air flow through the poly tunnel will also keep moisture loss to a minimum and so I cannot imagine that any water will be needed over the winter.

Poly tunnel frame, ground prepared for the bed etc. My mum wasn't overly pleased.

Constructing and choosing the materials was relatively easy. A little though was required to find the most cost effective way but carefully searching the internet and recalling some long forgotten physics helped.

The poly tunnel was purchased from ebay for £90, 4m x 2m, with careful packing it can fit a good sized collection. The heating element and thermostat were also purchased from the internet at a price of £80. A cubic metre of perlite and expanded clay was delivered to my door for £120. We had some old fence boards at home which helped but timber to build a bed can be acquired for £30. A fan heater £20, plus RCD breaker and extension cable for £10. The electricity used over the winter will be minimised through setting the thermostat as low as possible. In total, around £400 spent to safeguard the current financial investment and six, seven years of work and some future masterpiece trees....even if I do say do myself.

The bed was constructed and the path of the 25 m cable planned out. It was just as planned. The walls of the bed are old fence panels fixed together and held in by posts. It isn't the most permanent of structures but it will last the winter

A very thin layer of perlite was spread out over the base of the bed and the heating wire set out. On top of this, about 15 to 20 cm depth of perlite. If the temperatures were much higher, then over heating would be an issue, however we are aiming at minimal temperatures, just keeping it above freezing

I chose Perlite as the medium for the heating bed as it came out on top in several important factors; specific heat capacity, thermal conductivity and price per volume. It requires less energy to heat up, it retains heat and moisture incredibly well and is cheap. I will reuse it for my potting mix for freshly collected trees, whips, sick trees etc. I am a firm believer in Perlite for certain situations and having a cubic metre next spring is not a problem, I will keep the bed for problem trees I think. I topped off the perlite with a layer of expanded clay, slightly more expensive but heavier and larger particle sized, offering another layer of insulation and stopping the perlite from blowing away either from the wind or the hosepipe. The only issue with Perlite is the dust that comes with it, breathing it in is not a good idea, so I opened a hole in the bag, stuck the hosepipe in and made it damp. The hosepipe was used to stop any more dust from flying up when pouring out as well. A dust mask is advised.

All the trees in, some are buried in the bed pots and all, other stronger trees are left unprotected but will be wrapped when the weather turns.

You may notice that the deciduous trees are still in leaf and it is incredibly early to be preparing, however I am away almost all of October and there have been long range forecasts which predict snow soon. Better safe than sorry.

Heater and grow lamp. Heater is not pointing towards trees, on the lowest frost guard setting and on 1KW rather than the max 2KW setting. Lamp is above pines, junipers, yew and rosemary trees Still a considerable distance though, at most 1.5 m, closest is 1m

One other feature I have included which I have used every year in the smaller greenhouse is the grow light. A 250 W system which gives artificial sunlight, as close to the normal spread of wavelengths from the sun as possible. Why do this? All deciduous tree which lose their leaves do not need sunlight whatsoever and could be kept in a pitch black garage until close to spring time. Those evergreen trees which still have leaves are slightly different and require a little sun to see them happily through the winter. The idea is not to keep the growing throughout the winter, but just to keep the engine at idle and not stall. Once spring begins and we have natural sunlight, the trees start off quicker and grow much better. Mediterranean species and Japanese pines and junipers are not used to the grim Northern winters and so a touch of sunlight is essential for happy trees. It is not essential to keep them alive, but just to keep them happy I would advise investing in one. Prices start from £80 for a small system. I run mine on a timer, giving around 3 hours of sunlight a day, from November through until end of February. At around 1 Kwh of electricty per day that is roughly 15 p a day, lets say tops £20 a winter. The bulb has a tendency to blow or need to be replaced every four months, so thats another £15 a year. I'm still well under the £10k and years of work I threw away over the last few years.

Protect the electrics...the big white box is the ballast for the light. The other box is the thermostat. They are splash proof but use a safety RCD at the main socket just in case. With a 250 W heating cable, a 250 W light and a 1 KW heating fan, there is a lot of potential power going through there.

In conclusion...the basic rules for winter protection are to:

1. Keep the roots from freezing, expanding and dying. This is achieved by insulation and minimal watering. Regulate water intake, bury or wrap trees in something...even snow is better than exposure to wind.

2. Shelter from winds, especially the cold north winds

3. Allow the trees to go dormant. Do not over heat the greenhouse and keep the trees from going dormant.

4. Get as much natural sunlight as possible. Ideally supplement with grow lights.

Please give more consideration to the winter...even if it is just burying the trees in the ground, you don't have to go too far...just act now before it is too late.

Autumn is here...

It has been a while since the last post and I have been up to a few things, including another outing. This last weekend saw an interesting event in Crawley, namely Bonsai World 2011. It was the first time it had been held and was a good weekend, I got to meet up with the usual suspects and catch up, have a chat and look at some trees. There were some lovely trees on show, some at a high level, others not so, but all well presented and everyone had fun with it, which lets face it, is the point of doing bonsai. It was a well put together show and congratulations to all involved.

In an unusual turn of events I chose to put on a display, a favourite tree of mine was just about ready to go and it seemed appropriate to get it out. Although not quite in colour, there is a hint of red coming through there and it is perfect for the season as we are just about to start autumn and soon the leaves around us will be on fire...not literally I hope. The tree I displayed has previously been seen at a never to be repeated exhibition up North a couple of years ago around the same time. It is a sadly not often seen variety outside of Japan and one of my favourite trees...this Sumac or to be a bit more specific, Rhus succedanea.

It is potted in a Shidei or purple clay Chinese pot from around 100 years ago, there is no seal but it is a Meiji period design. It has been well used and has developed a good patina around the whole pot without sustaining any significant damage. It has taken on quite a shine which does not come from oiling the pot up before exhibiting which is something I am not keen on. The black lacquered board it is displayed on is the same one used in my Joy of Bonsai display a while back. I do have other boards, including a bamboo one I did think of using but it seemed slightly unseasonal and also clunky. The simplicity of the black rectangle appealed to me...and both Apple and Samsung apparently.

Only one person asked me why I didn't use an accent or a scroll, and the answer was that it didn't need it. The space was small enough as it was and the feel of the tree would have been destroyed if there was anything else going on there. To have created a busy display which conformed to a three item combination would have destroyed the simplicity of the tree and left it feeling mechanical and contrived. I had an ideal early autumn scroll but it was slightly too long and the colour too much of a contrast against the white back drop. It was a shame as I wanted to use it. I was happy to be on the end of the row as the extra space next to the display was helpful. It also helped to have some stones on the other side so I wasn't over powered by some massive tree.

The art of bonsai display is the art of successfully using space to create the impression of something larger than what is seen with the eyes. Space can be oppressive if seen with preconceptions of "tree, scroll, accent", there is a desire to fill it up. If freed from such self imposed conventions, the space can be liberating, allowing the viewer to imagine.

I am not sure how the displays that I have done in the past have been taken and I don't know if people expect for me to be displaying big impressive trees to show off my skills and professionalism and win prizes. I personally take the opportunity to show that there are alternatives, different aesthetic ideas and motivations for doing bonsai...

And then show off on the Blog.

Thanks to everyone at the show for making it fun, but especially to Simon Haddon who let me use his camera because I typically forgot mine.

If you think all the above is a bit pretentious and speaking in riddles, it's because I have been reading some books. Aye...proper ones. Been very enlightening.

"He who only knows, without seeing, does not understand the mystery. Even should every detail of beauty be accounted for by the intellect, does such a tabulation lead to beauty? ...The scholar of aesthetics...tries to make seeing proceed from knowing, but this is a reversal of the natural order. The eye of knowledge cannot, thereby, see beauty"

from The Unknown Craftsman by Yanagi Soetsu

So does that mean I wasted all my time reading books?

"A man should avoid displaying deep familiarity with any subject...it is impressive when a man is always slow to speak, even on subjects he knows thoroughly, and does not speak at all unless questioned."

from Tsurezuregusa or Essays in Idleness by Kenko

Oh...I will shut up then.