Added some pics of the Bord na mona j innes no 3 i use now , as you can see from the first pic i measured out 500 ml of the mix then added 5oo ml of water and left to stand for a hour then strained , you can see i have managed to strain just over 400 ml of the water back out of the mixture which is a good sign which in turn has left a well opened mixture and not a muddy claggy mix that i tend to have found with other makes. Have left the mass to drain over night in my workshop and will post some more pics tomorrow. Again it's trial and error with finding something your trees like to grow in without having constant wet feet. D couldn't have put the description better myself , basically a generic term for the compost but each company producing said compost using the "formula" or as near has possible to it. I definitely find this brand more lighter and free draining when mixed with my other components.
I’ve always used a 50/50 mix of John Innes no 3 and composted bark. The bark breaks down, composts sinks and water retention capacity reduces. Not a problem with regular root pruning and repotting, but if I can’t get round to doing this as regular as I’d like, I end up with a potting mix which has sunk signifying its pot and water retention capacity much reduced. Just wondering on what others are using with components I can easily source in the U.K as I’d like to trial a different mix.
Good morning J, I use John Innes no3, horticultural potting pine bark ( Melcourt), horticultural potting grit and Irish moss peat (Westland). Percentage of 30% of each and 10% of the grit as a general rule of thumb. John Innes no 3 has some grit in it but not enough IMO, hence why I add some more. I do wash this BTW. I re pot every two years, but this might go out to three depending on the root mass in the pot. But I do get a bit twitchy if left that long , Lol. D
Hi, my current mix is about 40% pozzolan, 30% composted pine bark, 20% pine bark chunks, 10% perlite. I don't measure, so batches vary a bit. I add mycorrhizae and a little osmocote. Repot about every 1/2 years as growth dictates. JMs do very well in this mix, some other maples like buergerianums don't like it as much. -E
For the basis of my mix for Japanese maples I always use about 25% of ordinary non-composted bark of the type sold for mulch, bought it from Wickes this year as it is just down the road. You have to chuck away a few big lumps of wood but no big deal. This takes many years to break down, much, much longer than the composted bark helping with the long term soil structure. I also want a component that will never break down so add around 5% each of perlite, horticultural grit and 10mm nominal grade gravel (pea shingle). That leaves around 60% which comprises of various proportions of John Innes No.3 or No.2, "multi-purpose compost", ericacious compost, composted bark etc. I avoid any of the compost lines that contains green waste but have used some good ones that contain "forestry by-products" and I try to keep a couple of different brands on the go and mix them. You get some stuff in "multi-purpose composts" these days that I have no idea what it is and it can be a bit of a lottery as most of the manufacturers are adapting their recipes to cut down on the peat content. For a long term mix I try to keep the content of peat low in any case as I find it does not age well and loses what structure it had fairly quickly. The mix is forgiving enough that if I am running low on one component I can usually compensate by adding more of something else to even things up. For instance this year I had loads of perlite but very little grit so upped the perlite and reduced the grit. For small pots I use essentially the same mix but try to sift out the larger bark pieces and maybe skip the large gravel. I don't measure any of my quantities, all the percentages above are guesstimates, I just eyeball it and if I end up with something like this I am happy:
I’ve been thinking I want to go back to using peat in the mix, in moderation. I always used too until we became aware of the Enviromental issues, but I do believe it’s of massive benefit in the mix with its water holding capacity.
Hi Emery. I can’t find Pozzolan available cost effectively in the U.K. Where do you purchase from, horticultural supplier or elsewhere? I’d like to experiment if it’s readily available at a cost effective price. JMs do very well in this mix, some other maples like buergerianums don't like it as much.
Hi Mas, your reply is interesting. I used to use John Ines no3 50/50 with small bark mulch chips and not “composted” bark. This didn’t appear to sink and when it came to repotting, the chunks were generally intact and not broken down. So the mix drains really well, but in addition when it comes to root pruning/repotting, it’s really easy to untangle and tease roots out. I switched to composted bark as every one was recommending it. I was also of the view that the wood content in the bark takes nitrogen to break down and hence stops excess nitrogen problems. Im wondering about John Ines no 3 with bark. Hips and peat and perhaps look at the Pozzolan that Emery recommended. I want an open structure so plenty of air and easy to drain, water holding capacity and a compost that does not sink as much as the composted bark appears too. A lot to ask and water retention with ease of draining spear contradictory.
I think of composted bark as a substitute for peat or "general purpose" compost, certainly in that category of ingredients. The regular bark mulch chips are a different beast altogether and as you say help the soil retain structure and drainage potential over a long period. very true
A few years ago I bought a tonne from a producer @AlainK recommended, near him. Called Terval. It is nice small grade, in France you can buy pozzolan in the big box stores, to use for bedding mulch, but the grades are too large for use in substrate. I'll need some more near the end of this year, actually. It is really great stuff, and has the added advantage of making pots hard to blow over.
From having worked in commercial practice here in the US growing woody plants including Japanese maples truth be told all that is needed is bark, sand and slow release fertilizer. With most of the combinations described above merely being unnecessarily complex variations on the same basic organic + mineral combo. With the sand serving primarily to provide a mineral component to the "soil" that is needed for the fertilization to be effective. And in fact when I worked in a wholesale rhododendron and azalea production operation many years ago we were potting evergreen azaleas in bark and nothing else, not even a mineral source like sand. With fertilization being accomplished by the use of a fertilizer injector during watering.
I have never left peat , still using the same mix and ratio when i first started. Never have any problems, saying that i have to travel a 16 mile round trip to buy my peat as most of the local garden centres etc don't stock it any more. Even chip my own bark to the size i like, need to get out more :) but my trees are happy and that's all that counts for me. Pictures of the trees are : Baldsmith, Summer gold , Shirasaw aureum and Autumn moon all these four cultivars were lifted in the same week in November 2020 and placed in appropriate containers with the same mix that i always use. Then the Mirte was lighted root pruned and again from it's previous container and moved up a size again 2020, then finally the Mizui kiguri this was lifted and containerised in 2018 same mix and three years later still going great, fantastic spring colours this year best i have ever seen. All pics of the trees were from this week , and they look all right to me ? My trees have two options when i lift and re pot them live or die it's up to them , to me the most important aspect is the quality of the root system (The engine) get this crucial part right and they will grow in almost anything you care to put them in , but this is just me i don't seem to have any problems with my growing mediums and won't be changing anything for sure.
I have experimented with sand, and for me it stays to wet. Even very sharp sand (river sand). What commercial growers can use is not necessarily suitable for life outside the greenhouse (or controlled shade cloth environment). I have grown in straight bark chip medium, but have found that smaller plants have a hard time "getting a grip". Once they get going, JMs certainly don't object to bark + osmocote, but this may not make the strongest plants in the long term (my experience again).
Mark, are you 50/50 wood chip/peat? I am going to start using peat again in my mix, just need to find a source locally. Your trees look beautiful, some of mine are starting to suffer in the heat even thou most are shaded
Tend to use 60/30/10 peat , chips , no3 and have started using a new brand called 'Bord na mona' did a small thread on this some months back now, but can't remember where?? not as claggy and heavy as a traditional no3 say like a Westland brand. Not having the serious hot/warm weather like the South at present so mine are looking reasonably well at present.
My goodness your trees are amazing @ROEBUK I recently increased my mini collection and was getting concerned I may a problem but you have shown me I just need to up my game!
@ROEBUK As previous posters have said your trees look great and are obviously very healthy and respond well to your style of root pruning and containerisation etc. (I looked back at an older thread where you showed some good pictures of the rootballs after attention.) My question is which months of the year do you prefer for root pruning and, perhaps more importantly, which months have you found to be unsuitable and why?
Thanks D knew someone would know where it was. maf will do you a detailed response tomorrow taken lots of pics today of trees which have been worked on over the past two seasons so you will see the results from when i work on all my trees.
@maf @ROEBUK and other contributors posted some really helpful info on this thread on rootpruning.. Mark’s photo’s of his root pruning techniques gave me the confidence to have an industrial go at some big ones..I’d previously only gingerly trimmed the root ball and found a bigger pot but it was getting ridiculous ..I’d previously been like that Vo5 Tv advert where the guy with thinning hair goes to the barbers.. Root prune - how much should be taken
maf further to your question re when do i work on all my trees, the basic reply is all my trees are started on in the fall months from October to December usually i try to have every thing done by the 3rd week of December , but have been known to go into early January it's just a case of seeing how wet the weather is at the back end of the year, have lifted trees in January when the sun is shining and the ground is so dry with no dampness ideal lifting conditions for me. Have never done anything in all the years of keeping maples in the spring time it just doesn't seem right to me, others will disagree and that's fine but they way i work on my trees in my opinion is a lot easier for me. Firstly if lifting a tree especially a large one to go into a container it's so much easier to dig out without the branches and leaves getting in your way, plus i can see what if any branches might need removing to give a better shape to the tree and i find i cannot do this if the tree is in full leaf. Some times if a tree is earmarked to come out in the fall i will do some light lower limb pruning to help with the shaping. Added some pics of a large Ki hachijo which was lifted last fall and you can see from the pictures what i mean by the pre shaping in late summer , this also helps cut down the stress on the tree when i come to lift knowing that no more limbs will be removed. I also find that i can manage the fall maintenance more easier with our temperate climate here in the UK , obviously i wouldn't attempt this type of work in countries which suffer from severe cold winters?? But saying this at the back end of last year i noticed certain things with the weather which made me stop in December and not continue any further into early 2021 just thought we might just have a horrible winter and spring and look what we had !!!! a shocker in the North of the UK , never seen a spring like this one just passed , and for me that is why i do all my work in the fall at least i know the ground temps are still on a milder footing and the newly lifted trees can cope with this. As to doing anything in the spring time i cannot really comment on this because i never do anything, it's all been done months before hand, i know lots of people do work in the spring with no problems but i like the Autumn month's when the trees are dormant. Saying that i did have to do an emergency lift in early May 2020 of two maples out of my nieces garden one weekend because the builders were starting to excavate her garden for a patio on the Monday morning , so lifted a large Tamuke yama and a Atropurpureum and told her they might not take to being lifted at such an early stage of the year, but said if they were not lifted they would be dug up and thrown away !!!!! Well dug them up and using the exact same methods on all my trees here are some pics of the trees back at their new home from yesterday , pleased with these and they took no problem.The picture of the trunk with the new growths ringed was from late September, seeing this growth told me that they would be fine for 2021. On a bonus note i bought her a Morrisons lock down special Tamuke yama for £28 they were practically giving them away during the first lockdown, saying if hers failed we had a back up plant to take it's place. Well both hers have taken well and the back up Tammy i get to keep and it's not looking to bad either, changed the growing medium again in the fall for this one.
Wow @ROEBUK thank you for the details it’s most helpful. I love your container garden and I love you use regular pots. It’s very hard for me to manage the ceramic one and I figured if the tree is beautiful it doesn’t need the distraction of a pot. Your trees are stunning. Question Do you insulate your pots over winter? Do you have any experience with grow bags? Your soil mix is chips, peat moss? Also do you ever use a sprays such as soapy water to control bugs and so forth? I believe I got rid of the cottony scale leaf from my Hana Matoi but want to be sure it doesn’t return. thanks again for all the details very inspiring since I’m trying to do the same thing in my yard.
