Myself, I would not bother with the dolomite. The dolomite would soon wash out rather quickly in a 5:1:1 mixture anyway. The peat portion (the acid portion) of the mixture in a 5:1:1 is only 14 percent of the mixture. Anyway, each to their own, its their tree, and their container mix, they can certainly grow it anyway they wish. Thanks for the reply. - Millet (601-)

Millet,

I'm a little confused. Are you suggesting Fir bark (likely Douglas Fir where I am) doesn't have a low pH? Or that it raises very quickly before a tree is put into it? Or that a low media pH wouldn't contribute to transplant shock?

I'd really like to know. I can understand the Dolomite would wash out which is likely why he suggests to let it "stew" for 2 weeks before putting anything into it (which would inevitably mean leaching by plant watering).

A while back, I recall a 2008 article describing western DFB, nutrients, and pH for container media. It all seemed to make sense about low starting pH and how lime increased the pH up to a certain point, but there was one vague line I didn't quite understand (due to a lack of background knowledge in the topic). It said something like the pH of unammended fir bark rose on its own from 4'ish to 5.7 in a couple months. But I was confused how that happened and it didn't discuss those details, such as the rate curve, what else was in the container (if anything) or even whether it was irrigated.

I assumed it had something to do with the composting process, since a small portion (put into a container) was removed from the giant pile, the exposure of excess oxygen, etc.

Chris

That tree has had it....start again and make sure you get a nice blend of organic and inorganic materials....I found perlite is very good for increasing the air spaces in the mix.What happens on the top is a reflection of whats going on underneath= compaction,lack of oxygen and water logging....Been there and done that so many bloody times! goes like this= some leaf fall,maybe with curling leaves from the bottom up and once nearly all the leaves have died...then twig die back.
when you remove this dead tree from the pot all the roots will look yuk and half of them will break off in the mix. I must have done this at least ten times and i feel your pain

One other thing...how big was the rootball when you transplanted it in relation to your present pot? I killed several of my trees by transplanting from a 20cm pot that it came in into 35cm pot.....It should be 1 to 4 inches bigger than the rootball.....If it goes into too big a pot...there is a lot of soil around the outside that doesnt get used by the roots and stays wet/becomes stagnant and therefore encourages root rot.......Over the past three years i have repotted just before spring
1. 20 cm to 25cm
2....25cm to 27 cm
3. 27cm to 31 cm
4.This year 31cm to 37 cm..............Has been working well and i have had no failures

Hi,just wondered if this tree survived to grow another day or did you abort and start all over? Cheers

What tehnique do you use to repot in just an inch or two space , I can not get my finger inside

Dan...True a 31 to 37 cm pot doesnt sound much...but that is only the diameter of the top of the pot. when i lifted out my dense rootball and put it from the 31 to the 37 there is quite a bit of new space...especially in height...In fact if you stand the 31 cm next to the 37 the 37 looks a lot bigger.It feels it when you lift it up too mate
My trees are loving terracotta but as they are getting bigger,i will need to keep up my weight training i think...At least they wont blow over in the wind!

Thanks for explanations , but you didn't told me how do you add soil on the pot in such a small place


I forgot to say that I use only nurseries pots , cilindrical shape.

just add about 3 to 4 inches of soil add the bottom of pot....put your tree on top of that and then fill all around with new soil...put tree in at same height as previuos container.....use a pot with a slight V shape

Thanks , I will try to use some V shape from now on , as possible