kitty litter?

Great tree with a great future. Thanks for posting them all and the info on soils. You could have made a separate thread with the trees. Make a development thread in the future.

Interesting points.

Perhaps the message IS, that a totally homogeneous substrate may be the problem - be it Akadama, calcined cat litter or whatever.

Thinking about the 3 major tree deaths I have had - one a Harry Harrington original , a mallsai elm that I had brought on leaps and bounds to a very decent shohin and a lonicera hedge rescue - I recall that they were all planted in 100 % cat litter (Tesco) which I chose for cosmetic reasons. i.e. potential show trees if I ever join a club :-) coupled with them all being in decent Erin pots.

They all collapsed around late March/early April 2009 with zero new roots showing and little old root in evidence.

At the time I put it down to wet pots caused by the comparatively fine grained Tesco litter ”locking” together with “fines” into a mass and/or poor re-potting technique.

I have also nearly (and maybe still HAVE) lost the one bottom right over the past winter and this had also been in a Tesco mix for the reason above.

It was transferred to a pond basket end of the winter with a Sophisticat/Grit mix and seems to be re-budding although all the majority of the original branch structure as pictured, has died off.

I've always felt it "dodgy" instinctively to use a single-medium substrate and 99% of the time employ a mix of Akadama (though not much of that left now), Sophisticat Pink/Tesco cat litter , Hydroleca 10mm, horticultural grit (granite) and Soil conditioner (composted bark)

So maybe we should be specific and be steering people away from 100% reliance on calcined cat litter or akadama or whatever, towards a more random 2-5 component mix.

fwiw

Thks

TimR

I am very sorry to hear that you have lost trees.

Whether it is due to what I described previously, I know not, but as I stated earlier, winter protection and very careful watering regimes are needed. I have not said to anyone do not use cat litter, what I have said is that one has to be vigilant, as a result of my own hard won experiences I thought it proper to share to the wider audience what could happen.

Of course my experiences only appertain to the UK, not the far flung reaches of the world that some of my critics come from, they must draw on their experience.

Dave Martin wrote:....as I stated earlier, winter protection and very careful watering regimes are needed. I have not said to anyone do not use cat litter, what I have said is that one has to be vigilant, as a result of my own hard won experiences I thought it proper to share to the wider audience what could happen.

100% spot on advice Dave.

If you're at Wessex on Sunday, show me where the main exhibition room is!




thks

TimR

Hi Dave,

I understand all the points you have very clearly described, and i agree that for areas like yours, where frost is an issue, protection of the trees is mandatory, no matter what substrate or mixture is used.
In my climate, frost is not an issue, but the heat is an issue, and substrate mixtures that withhold moisture are ideal. I find Biosorb/terramol very good for this purpose, with only one drawback if used with sphagnum peat moss...the pH, which becomes slightly acidic and needs to be addressed somehow. I have very good root growth and all the trees seem to like it.

By the way, you have some very nice trees. Thank you for sharing.

Interesting information i have found which would actually support one of the points Dave has mentioned:

When the water freezes, its volume increases (by 9%). A porous material when saturated with water, will expand upon freezing. If its mechanical integrity is not good enough, the particle will dissolve. In substrates where there are small particles (like dust), drainage is not good enough, and water is trapped in the air spaces, making the problem ever worse.

Cryosuction...(now thats a relatively new thing.......)...in freezing soils, the water migrates from the pores of the substrate particles (via capillary action) to the spaces around the grain and it freezes

Terramol (Biosorb) retains up to 108% (Westinghouse) of it’s own volume of water (by the way, i think it's cheaper from the same product used as cat litter and it's purpose made for horticulture). Other materials with less porous surface, retain less water.

All this means 3 things for me:
1. "softer" substrates like akadama, cannot withstand the repeated expansion and they dissolve
2. for areas with lots of rain and freezing conditions, a mix of porous and non-porous material is probably better to avoid the root damage.
3. in areas like the place i live (CYprus) where the temperatures may reach up to 45 C (last year all August we had higher than 38C!!!) the use of Terramol or other highly porous products is ideal, since it retains lots of moisture and releases it when needed from the roots.

Thanks for the information Stavros. Have never used Sophistikat on its own and certainly won't in the future.

stavros wrote:
All this means 3 things for me:
1. "softer" substrates like akadama, cannot withstand the repeated expansion and they dissolve

I live in Eastern Pennsylvania zone 6a. I started using akadama 2 years ago and was told the same thing. We have just had one of the worst winters in years and my finding so far is that the only akadama that breaks down is on the surface...the rest in the pot is intact after a brutal winter. I will add that I am using the double red line akadama which is the harder variety.

Cryosuction eh? Makes sense

I noticed a significant amount of frost heave in all of my cat-litter-heavy pots this winter which was very cold for a spell but no real snow as opposed to last year which was lots of snow then quite cold for a spell.

However, no noticeable tree damage this year or last. Winter 2008-9 was the bad one for me.

TimR

Paul Landis wrote:

stavros wrote:
All this means 3 things for me:
1. "softer" substrates like akadama, cannot withstand the repeated expansion and they dissolve

I live in Eastern Pennsylvania zone 6a. I started using akadama 2 years ago and was told the same thing. We have just had one of the worst winters in years and my finding so far is that the only akadama that breaks down is on the surface...the rest in the pot is intact after a brutal winter. I will add that I am using the double red line akadama which is the harder variety.

maybe because the outer layer of the substrate is more exposed to the environment compared to the core???
if it breaks down on the surface, it will eventually break down deeper as well.

Stavros,
Thanks for the effort you have put into researching the point I was trying to make and the additional info regarding cryosuction.

It is very informative.

Dave Martin wrote:Stavros,
Thanks for the effort you have put into researching the point I was trying to make and the additional info regarding cryosuction.

It is very informative.

U r welcome!!
All the effort we put here is to share our experiences.
We should always take into consideration the variations of the climate and microclimate of the area that each of us live in, since it makes such a difference not only to the species we can grow, but to everything else as well (substrate, time of repotting/pruning/collecting etc). This is something that we sometimes tend to overlook...

Thank you all and everybody for your efforts an research and for sharing your knowledge and info here on IBC with the rest of us!