Yeah… growing with rock wool is fairly inexpensive. I only have about $5 invested in the rock wool I’m using for the Leftover Seedlings grow by using the stacked 4” cubes. I’ve been buying cases of the 4x4” cubes, 3x8x35” slabs and the 3x12x35” slabs to save a little money; however since the 6x6” slabs are capable of growing decent sized plants I’ve decided to stop buying the 8” slabs and stick with the 12”. I can cut 10 individual 6x6” slabs out of the 3x12x35” slab and then wrap them myself to save money.I'd be using the 3L airpots.. so a bit under a gallon.. the cost is so little bro.. the 4x3 inch blocks were 50p and the 3x3 inch 35p.. got 10 blocks and 12 starter plugs for £5/$6the cubes I couldn't quantify but they are very cheap indeed given how far they stretch.. the 3L airpot set up would be no more than £1 per pot and likely less.
I'm really taken with somehiguys 2 daily feeds from day 1.. and he hammers that point.. so that's what I'm gonna try to replicate with blocks cubes and airpots.. I really do think I should only do 4 tho.. If they grow like they should im sure 4 will fill my tent.. all that said I may go blocks on blocks or pick up some hugos..
Also I was thinking a safety net of a few soil plants as well.. or do I just go right at it shit or bust all grodan.. thinking out loud now just.. Still lots to be considered
Would be very interesting to watch you grow 4 monster plants in your tent by using somehiguys method. (no soil safety net needed) lol
I’m basically doing the same thing with 6 of the late flowering plants that I took out of my tents and they’re doing just fine. I’m sure you can grow some nice large plants by stacking a 4” on top of a 6” Hugo or a crouton filled container. The GG4’s I have in my 5x5” are only in the 6” Hugo blocks and those plants are big.
Glad you’re putting some good thought into this buddy. It would be nice to see more people growing autos with rock wool.
either that or there's a lot of old folk growing Lilies 
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