The compost below is the current mix we use! I have posted this mix before at uk420 but have been asked about it several times so I’m going to pin this thread for a while to make it easy to find.

This mix cross relates to a current experiments being run. This is using a different light combination re a 600w MH made by venture and a 400w son-t plus by Phillips. The hoods/reflectors are also a new type we are trying.

The majority of the plants are in our standard mix but 8 are in Bcuzz bio-terreno and a few in in a test mix we have made.

This main grow mix is one we have developed over the last few years. I can’t recommend enough the organic base fertilisers produced by Jetze’s Bio Bizz company. In this latest mix we have 1. removed the perlite, the dust from this product is now thought to be carcinogenic in the same way as the dust from rockwool and glass fibre products are. 2. We have also removed both sedge and moss peat and replaced it with coir. Coir [coco fibre] is a renewable resource unlike draining and removing peat from sites of special scientific interest.

We use sog with selected sativa dominant mother lines. 5.5 or 6 litre sq pots flowering time 9 to 12 weeks by variety. 48 plants per KW of mixed lighting. The yield is between 48 and 56 ounces 28 to 33 grams per plant, the area = 5 x 4 ft.

Compost per 50 litres [When settled in pots]

Every thing is riddled through a 1/4 inch sieve

25 litres of coco
12 litres of sterilised organic Kettering loam
8 litres of Bio Bizz wormest
5 litres of Bio Bizz premix
200 ml of dolomite lime
300 ml of Calcified seaweed
100 ml rock phosphate

For details on capillary matting mylar roller blinds surrounding the grow and more info take a look at this:- link [link removed as og is gone.]

Generally grow shops are on big margins so if you get together with other growers in your area it can be a lot cheaper to buy bulk. ie importing coco a pallet load from bio biz it works out at about £4 per 50 litres.  It is important that any coco you use is washed so it is low in sodium but not ph corrected and stabilised ie use a pure product and not a chemically treated one.. Coco has a symbiotic fungi in it called tricoderma, it helps protect the roots of cannabis from things like root rot fungus [pythium]

With the 48 baby cuts grow we are looking at a couple of things.

Firstly will changing from a 600w sodium and 400w halide to a 600w halide and a 400w sodium reduce the average yield of our standard plant mix re each var. Will the new reflectors overcome the lower yield found in the corners of the room. How will the Bcuzz compost do against our standard mix that costs a quarter to make.

Finally there are a few test clones in the plant mix. Will they be able to keep up with our standard mother lines. We know from a seed grow that they are connoisseur quality as far as the buds they produce but at the moment it looks like they will disappear under the canopy of our standard lines if so its the compost bin for them.

A final note the Bcuzz compost is very light in weight, if it does well in this test it may well be of interest to med users who have trouble moving heavy compost and pots.

Edit to add I have gone back to a much lighter fertilised mix, half what I had been useing, and dropped coco for the time being.

To make 50 Litres of compost
15l moss peat
10l sedge peat
10l loam
7.5l perlite
5l wormest.
2.5l premix
Dolomite lime 300ml
Calcified seaweed 150ml
seaweed meal 100ml
Rock phosphate 50ml

Great content.....I think I'll save that over here.....Thanks WM

What was the conclusion OT?

The coco based compost yielded less by 7 to 12% than the same base using moss and sedge peat. Plant health was not maintained as well and the coir need more watering.

Then we got a bad batch of coir that still had some salt residue, I'm wading through the remaining half pallet load with things that don't mind a bit of salt like beetroot and kale etc.

Its still an ongoing project, but on hold for the moment, we have gone back to using peat and perlite.

Yield is 3 to 5% higher with the 600 sodium 400 halide combination against the 600 halide 400w sodium combination. Little or no height/stretch difference between the the two light combinations.

But buds grown under the 600w halide 400w sodium combo were slightly less dense, there are not as many trichomes but its much more oily and very noticeably more psychoactive with every variety in side by side smoke tests. The aroma is much nicer and the flavour when smoked is better as well using this light combination.

Bcuzz bio-terreno produced worst plants and results I have ever had 0 out of 10.

Take these as interim comments, research its still ongoing.

UK420, truly the cutting edge of cannabis cultivation (sorry, that sounds like a piss take but I mean it sincerely)

Respect to you OT1 - I'm sure each & every member here owes you at least some debt of gratitude for your work & advice

is the project still on hold?.........

Its still an ongoing project, but on hold for the moment, we have gone back to using peat and perlite.

Hiya. Yes I am back and will soon be ready. Questions. What ratio of peat to perlite per 25 liters?
I have been thinking, I take it that the coco/coir/peat is just to add body and to get the PH down. Exteremly well composted back should do the same job it's Acidic and more free draining the peat or am I barking up the wrong tree?
Look forward to hearing your views on peat replacement Ot1.
Pete

great post OT1

cool link as well!

have you thought about track-mounted lighting re the low corner yeilds.
runs along track to a timer?



peace

Ng.