For Sr

[oldtimer1]

Hmm a bit of compost science myth and magic, ramblings for sr to take to bits and play with.

The advise going back over a hundred years, was to crock pots to improve drainage and stop compost seeping out of the pots and keep worms out. All has proved to be totally wrong.

Especially with the advent of capillary beds or matting. What you really want is the same medium going from the top to the base of the pot so its capillary profile constant without a break. If you want to change the water/air/drainage capacity of a medium it is best to change the whole medium.

For the most healthy root profile, it is best to water with a fine rose over the entire the compost surface untill you get run through, this oxygenates the water/feed when applied, it also drives stale and toxic gasses down through the rootball drawing in fresh air as it drains down from saturated to its natural holding capacity.

It has been found that crocking pots rather than helping drainage to the surface a pot is standing on, in fact it inhibits it. This means whatever potting medium you use holds more water and less air than its natural capacity, the thicker the crocking level the worse the problem.

The best growing results come from a wet dry cycle, by dry I mean down to 5 or 6% of the composts wet capacity, if you go much lower than that the root ball will shrink away from the pot walls killing a large percentage of the fine feeder roots, you don’t want to do this as it sets the plant back and every time you do it, it will reduce the final yield a bit more. Another problem where a rootball is allowed to dry out to the shrinkage stage is that it is very hard to wet it properly again, What happens is the water runs off the surface and down the gap round the pot edges leaving 70% of the rootball dry.

If your plants are on a sand/matting bed providing there is no crocking the odd over dry rootball will fully rehydrate its self from the bed after the area has been watered.

It is not a good idea to water or feed from a capillary bed unless you have a very very open medium, if you are going to do this you might as well grow hydro.

Where the myth about needing 30 to 70% perlite in compost an an ideal medium for growing cannabis came from:-

In the early days of cannabis growing in the states, the heads growing indoors did not have a clue about gardening or horticulture at all. They wanted to grow plants like outdoors, big plants, so they would use a big pot 10 to 50 gallons fill it with a couple of bags of Schultz container compost, water, sow a few seeds.

Now we all know what happens to 10 gallons of saturated compost in an enclosed container, with no roots to pump the water out and just a little surface evaporation, within a couple of weeks the whole mess goes anaerobic and sour. To compound the problem, the surface dries so they keep watering the seedlings that in turn get sicker and sicker as root fungus get a grip in what is now an ideal environment for it.

Did they look at what the plant industry did? No they were growing cannabis they had to resolve the problem, they stuck with big pots. One method was to fill the pot and just use a tiny amount of water around the seed. Of course this meant watering several times a day as the surrounding compost sucked up the water. Then they tried adding more and more drainage! Grit, sharp sand and finally perlite. Until the 10 gallon pot was only holding 3 or 4 gallons of compost and the rest was inert filler ie they were nearly growing with just water and nutrients. They never learnt about standard potting on techniques or considered them irrelevant or too time consuming.

Even today 40 years on, where large pots and huge plants are no longer the thing. Then the firm belief was that for optimum yield you should not grow more than one cannabis plant under a 1kw light, no one even thinks about that now, its laughable.

Yet we still see people adding large amounts of inert perlite and vermiculite to compost. It just goes to show what a tough plant cannabis is, as it often survives and crops despite the things that are done to it. Its not done any where else in the horticultural industry. So why oh why, when its a completely groundless bit of nonsense does it still hang on in the cannabis world.

[Bish]

Nice one OT

[vek]

brill,, the more i read your threads the more i think off going back 2 soil.

[Serj]

Nice timing ot.

Bish just posted this link on one of my Q's and it seems to have answered some of my problems. My Q

Cheers

J

[sittingrelaxing]

It has been found that crocking pots rather than helping drainage to the surface a pot is standing on, in fact it inhibits it.

that's me latest plan tits up.....

It just goes to show what a tough plant cannabis is, as it often survives and crops despite the things that are done to it.

i am more a lucky grower than grower, i've only ever grew cannabis and cress,(at school)

If your plants are on a sand/matting bed providing there is no crocking the odd over dry rootball will fully rehydrate its self from the bed after the area has been watered.

thanks ot, that suits me better,hadn't thought of that...

a very imfomative post as usual, ot,

cheers

sr

[Wilbur Nutsack]

Back to the

Hope you never wasted too much time sewing SR

[Bish]

[sittingrelaxing]

[bumpkinbwoy]

Another good read OT - Thanks

[Natporucnik]

Nice one OT

Cheers mate

Nat

[Muppet]

Can someone please help my muddled mind here please?

Bear with me 'cause i'm mullered and confused. It's this talk of a media becoming 'anaerobic' that's confusing me. Now bear with me but, when i was a keen collector of catfish and had aquariums everywhere, the nitrogen cycle was a very important thing to me and anerobic bacteria were the good guys 'cause they're responsable for the final part of the nitrogen cycle, which is breakin' down nitrites to nitrates which were less harmful to fish and absorbed by aquatic plants. So what i wanna know is, do aquatic plants and non-aquatic plants absorb nitrogen from diferent parts of the nitrogen cycle or is an anerobic media not related to types of anerobic bacteria?

p.s. I'm relightin' this spliff and hoping this makes sence!

Edited May 27, 2005 by Muppet Paster

[sittingrelaxing]

p.s. I'm relightin' this spliff and hoping this makes sence! 

366553[/snapback]

and here's me Doutin' my spliff so i can try and understand the question...

[MDP]

pmsl.. i aint got any usefull input

but maybe theres some fishy characters on this site that have

[Muppet]

[MS?MJ!]

Can someone please help my muddled mind here please?

Bear with me 'cause i'm mullered and  confused. It's this talk of a media becoming 'anaerobic' that's confusing me. Now bear with me but, when i was a keen collector of catfish and had aquariums everywhere, the nitrogen cycle was a very important thing to me and anerobic bacteria were the good guys 'cause they're responsable for the final part of the nitrogen cycle, which is breakin' down nitrites to nitrates which were less harmful to fish and absorbed by aquatic plants. So what i wanna know is, do aquatic plants and non-aquatic plants absorb nitrogen from diferent parts of the nitrogen cycle or is an anerobic media not related to types of anerobic bacteria?

p.s. I'm relightin' this spliff and hoping this makes sence! 

366553[/snapback]

Hi MP, just jumping in cos it's fish-related but I think you've got it the wrong way round there - I also have aquariums and it is the beneficial aerobic bacteria that drive the nitrogen cycle, they live in the greatest numbers in the filter media which is why it needs to be kept oxygenated at all times.

The anaerobic bacteria are the bad guys in the aquarium, they create poisonous by-products by their action once they establish themselves, which is why if you have sand or gravel as a substrate you need to keep it stirred/turned over regularly so the anaerobic bad guys have nowhere to get a foothold

Not sure if that helps at all but hey, I'm a fish geek

msmj