C
Coronel
- 61
- 18
Hi Sea thanks!
Going to try to reply to all the topics touched, but please bear in mind that the big plant died before this post, it is mentioned and there are picts just because it is the mother of the clones that are trying to survive...
Run-off / Slurry pH methods:
I do the slurry and the run off and trust them both (what I don't trust is this grower who seems unable to follow step by step instructions...
I prefer in those cases the run-off as you get a somehow homogenous average of soil condition/pH
As you mention the slurry is good, but only if not only is taken from at least several levels of the medium, also it really needs at least a few hours so the elements mix and react with whatever they are going to react in order to get a representative sample of the real pH.
After digging a little he was doing top soil sample, shaking, filtering, using drops.
He conveniently forgot to let it sit for at least 1 hour.
I did a run off and a slurry with 24h resting time from the soil of the dead plant, with both i got a color corresponding to something between 6 and 7 (those drops are not accurate for in between values...
When @Homesteader speaks of Salt toxicity i assumed we was talking about remaining minerals in the soil from water evaporation. And I think that his old soil might have been saturated as he waters with tap water and water in our city is very hard.
I never had the need for a pH meter, but after seeing this i decided to get one for me (who knows how can i use in my organic food operation...
I have never found litmus with a pH decimal precision (i.E: 6.7 they usually are like the drops, integer numbers and before the "hippy acidic basic food fashion" one could only find 1-14 litmus, in europe now most litmus commercially available are just basic/acid color i mean one or the other no actual reading, so i ordered a chinese pH and Humidity probe.
The Ficus: that is me, i use the mix for those and most of my green decorative plants and i have a green forest at home.
If you look a few posts back i discovered he asked me for a soil mix and made a different one (which is particularly water retentive) but he kept the water schedule i gave him for my soil mix...
Here is an interesting link about Perlite and Vermiculite.
http://homeguides.sfgate.com/difference-between-perlite-vermiculite-71758.html
"They differ in their ability to buffer pH changes. Perlite is rated as low in its capacity for pH buffering, and vermiculite is rated as high. Although both can hold plant nutrients such as those in soluble fertilizers, perlite has a low rating and vermiculite is rated as high. Perlite contributes no chemicals or substances to the soil mix, but vermiculite can add potassium and magnesium."
Something to take into account is that inital use of Perlite and Vermiculite was to create thermal + noise isolation, later they started being used to make light concrete and eventually someone discovered it could be used for plants...
At that point there was a split, the building industry needed hydrophobic materials to make sure water from the concrete did not migrate towards the P/V"lite" because you want water in the concrete to evaporate not to be trapped... Vermiculite stopped being used and perlite took off, until someone else discovered that firing the vermiculite at very high temps, under slight vacuum conditions it becomes slightly hydrophobic.
Where we live you find mostly building vermiculite (and it is way cheaper than the agricultural one (15€ a 100 lt bag against 25€ for 6 lt bag for plants...)
Also the building one is the same formula but it is hydrophobic so acts as perlite (Which you simply cannot find in here anyway)
Vermi is basically Mg, Fe, Al, Si, O I think i read somewhere that it helped make Potasium mobile, but cant remember where or when so i cant confirm.
I know that the chemical formula for unexpanded vermiculite is the same as a mica but the Potassium ion is replaced by Mg and Fe
In any case in his mix there was no Vermi or Perlite, he used hydroton +old used soil + horticultural bag.
I think the reason the mother plant survived so long was that in the small grow chamber his 600W hps was putting so much heat that some of the soil was not saturated and some roots could survive... once he moved to the bloom chamber which is bigger he lost around 7C and the roots were oxygen deprived. (Even thou the dead plant shows healthy root system it was not as big as it should have been for the size of the plant.)
