Rockwool F&D: Managing Roots

Recently switched to 4" (10 cm) Grodan cubes to run my SOG from clone to harvest.

Method:

1. Place cuttings in root riot cubes until roots coming out (5-7 days)
2. Place root riots into the rockwool cubes, veg until roots come out of the rockwool (4 days)
3. Place rockwool cubes straight onto F&D table, start by feeding once a day, increase to 3x daily for now (crop steering so I have lights on at 10am, then feeding at 12, 14, 17h).

My question: How should I manage these roots? They are starting to spread out from the rockwool cubes and into the light, will/should they prune themselves? Should I put a coco mat or some hydroton on the table itself to give them a little cover?

I am hesitant about the coco mat since it would hold a lot of moisture and I want my rockwool to dry back as fast as possible so I can increase my feeding frequency.

The plants look fine as is, but this is my first time doing rockwool so IDK what to expect. (actually, this is also my first time in coco as well, but I switched to rockwool for the second half of the table since the small cubes are cheap and less of a pain to deal with than bags of coco and hydroton).

Welcome advice from experienced rockwool growers!

P.S. A couple of nug shots from my second ever grow in a 90x90, things have escalated quickly haha

I do a slightly different style of flood and drain ,i use 50mm growdan blocks and and buckets that flood via a bell syphon. Pump runs constantly .
I get great results but its a bit different to your set up so advice wont match .
Its here if you want a look you might take something away from the process i use.

lodaweed said:

My question: How should I manage these roots? They are starting to spread out from the rockwool cubes and into the light, will/should they prune themselves? Should I put a coco mat or some hydroton on the table itself to give them a little cover?

Click to expand...

Back years ago i used to run clay balls (hydroton) under panda film on trays with 4inch grodan blocks but i wasnt 100% happy with it ,the shallow trays and bright warm lights made root zone a little warmer than i liked .
Thats why i chaged my set up plus hydroton is labour intensive to clean between grows . If you use matting its not going to dry fast enough for frequent watering cycles that you want (need) .
I see your dilemma

Absorber said:

I do a slightly different style of flood and drain ,i use 50mm growdan blocks and and buckets that flood via a bell syphon. Pump runs constantly .
I get great results but its a bit different to your set up so advice wont match .
Its here if you want a look you might take something away from the process i use.

Click to expand...

Really interesting setup, I guess it’s more of an RDWC / NFT in that your water is always there and oxygenated. Since im doing practically zero veg, I need 50-60 plants to fill my 1.2x2.4m table, upside is I can harvest every 9 weeks.

good to hear about your experience with the pandafilm, I guess it also doesn’t help the cubes dry out any faster… I’m thinking of leaving them roots exposed for now and see what happens.But I’m thinking if I just poured a couple bags of hydroton on the flood table around the 4” cubes, maybe the roots could spread even more and have better results.

lodaweed said:

Really interesting setup, I guess it’s more of an RDWC / NFT in that your water is always there and oxygenated.

Click to expand...

No my buckets continuosly fill and drain so roots are exposed then covered then exposed and so on and so on it doesnt stop .
So i see it as a flood and drain only difference is theres no timer and pump doesnt stop the bell syphon controls the cycle .

They should air prune. I wouldn't do a thing.

pegboy said:

They should air prune. I wouldn't do a thing.

Click to expand...

Thanks, have you run this type of system before? could I get more roots (=more fruits) by covering in hydroton?

lodaweed said:

Recently switched to 4" (10 cm) Grodan cubes to run my SOG from clone to harvest.

Method:

1. Place cuttings in root riot cubes until roots coming out (5-7 days)
2. Place root riots into the rockwool cubes, veg until roots come out of the rockwool (4 days)
3. Place rockwool cubes straight onto F&D table, start by feeding once a day, increase to 3x daily for now (crop steering so I have lights on at 10am, then feeding at 12, 14, 17h).

My question: How should I manage these roots? They are starting to spread out from the rockwool cubes and into the light, will/should they prune themselves?

Click to expand...

I air-prune my 4" blocks on a wire mesh for a few weeks and what this does is create a huge massive root ball that explodes with roots when it eventually hits my NFT

lodaweed said:

Thanks, have you run this type of system before? could I get more roots (=more fruits) by covering in hydroton?

Click to expand...

Pretty much my entire growing career has been with various ebb and flow systems in rockwool. I guess bigger roots bigger fruits to a degree but with hydro it doesn't make a huge difference because you can feed them all the nutrients necessary to keep them healthy in smaller areas. I recently started growing with 6x6x4 blocks and yes have gotten slightly bigger plants in the same time frame but at the same time I just grew a 40-in plant out of a 4x4 rockwool cube. It wasnt optimal but it worked just fine.

And after going back and reading your original post, I think 4x4 cubes only would be just fine with your time frame. No problem at all

pegboy said:

And after going back and reading your original post, I think 4x4 cubes only would be just fine with your time frame. No problem at all

Click to expand...

thanks bro appreciate it