Club Rockwool

As there is not too many places to learn about growing using Rockwool as a medium from start to finish.

I feel a central thread to show our methods and techniques would be quite useful.

I'll start!

At the moment I use grodan Rockwool starter cubes once my seeds have popped using the paper towel method. I transplant up to the three inch cubes trying to achieve as much air pruning as possible. I then just stack that cube ontop of a 6" Hugo.

I don't use any automated watering, preferring to hand water 1-2 times a day.

In between stages I use mykos and azos from xtreme to help give some healthy white roots. I use tap water and floranova nutes and this seems to be working well.

Previously I was using the small croutons after the 3" got root bound. I may switch back to this method as it allows me to be flexible with my pot sizes, and root mass'.

How many of you also use Rockwool to the end?

Using Grodan chunks with my ebb and flow. I veg on a table and then plop them into my buckets for flower. Veg is a little tough since rockwool doesn't hold the plants up as much as hydroton, but not an issue in flower since I'm using a trellis. I switched to rockwool because hydroton is a bitch to clean

ThaMagnificent said:

Using Grodan chunks with my ebb and flow. I veg on a table and then plop them into my buckets for flower. Veg is a little tough since rockwool doesn't hold the plants up as much as hydroton, but not an issue in flower since I'm using a trellis. I switched to rockwool because hydroton is a bitch to clean

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Have you found issues with rockwool with ebb and flow? I have considered switching to it but each of my plants tend to drink at varying rates and I don't wanna flood em.

JDMase said:

Have you found issues with rockwool with ebb and flow? I have considered switching to it but each of my plants tend to drink at varying rates and I don't wanna flood em.

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Holds more water but so far so good

I love rockwool. Clone or seeds in 1.5" starter plugs, once they've rooted(about 10-14 days for clones) I stick them in Pargro 6" cubes. I like to use a Myco Jordan slurry for transplanting. Seems to stimulate root growth and keeps the roots really healthy.

mjinc said:

I love rockwool. Clone or seeds in 1.5" starter plugs, once they've rooted(about 10-14 days for clones) I stick them in Pargro 6" cubes. I like to use a Myco Jordan slurry for transplanting. Seems to stimulate root growth and keeps the roots really healthy.

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I love using mykos! Never looking back!
How do they do going straight into the 6"? Do you keep them there or up size?
Am I right in saying pargro are the quick draining blocks?

Im concerned my biggest Kings kush has become root bound and im not sure whether it needs more Rockwool or whether I can get away with just feeding it more? I have drooping leaves and the cube is usually dry after 16 hours but everything indicates over feeding. My nutes have gone from 500ppm down to 300ppm as I hit some nute burn tips.

EDIT: I think the above issue is nitrogen toxicity, gonna leach with low nutes

Still working this medium out love it though!

ThaMagnificent said:

Holds more water but so far so good

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Which ebb and flow system to you use? I'll check it out if you recommend it!

JDMase said:

Which ebb and flow system to you use? I'll check it out if you recommend it!

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I veg in a table. I flower in the buckets by hydofarm/active aqua. I run suspended 1 gal so I veg on the table and then plop the 1gal into my buckets for flower by using a styrofoam board on top of the buckets

JDMase said:

I love using mykos! Never looking back!
How do they do going straight into the 6"? Do you keep them there or up size?
Am I right in saying pargro are the quick draining blocks?

Im concerned my biggest Kings kush has become root bound and im not sure whether it needs more Rockwool or whether I can get away with just feeding it more? I have drooping leaves and the cube is usually dry after 16 hours but everything indicates over feeding. My nutes have gone from 500ppm down to 300ppm as I hit some nute burn tips.

EDIT: I think the above issue is nitrogen toxicity, gonna leach with low nutes

Still working this medium out love it though!

Click to expand...

I only go to the 6" cubes, I considered getting slabs to lay them in but haven't run into any problems yet but I run quite a few cubes in smaller spacing so don't grow trees. Pargro are the quick draining cheaper cubes. I think if you buy in serious volume(say a container) you can get the price down to about $1.20 a cube. My watering schedule is four a day during lights on flowering and I find the cubes stay moist but not over saturated and never really dry(in veg I let them get drier to help stimulate root growth).

Anybody got any tips on whether you should upgrade from a 6" Hugo into anythin else? Im on two top feeds a day with a plant pushing 1 metre tall. Roots completely saturate the medium and the leaves look like they still have nitrogen tox despite me flushing, leading me to think that it's "root bound"?
I could fill a pot with the crouton cubes and let them stretch into that, I don't know how roots grow in the flower period but im guessing they slow root growth to a stop. Cheers

JDMase said:

Anybody got any tips on whether you should upgrade from a 6" Hugo into anythin else? Im on two top feeds a day with a plant pushing 1 metre tall. Roots completely saturate the medium and the leaves look like they still have nitrogen tox despite me flushing, leading me to think that it's "root bound"?
I could fill a pot with the crouton cubes and let them stretch into that, I don't know how roots grow in the flower period but im guessing they slow root growth to a stop. Cheers

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grodan has mini slabs you can now buy for about $6, one is perfect for under a 6" or you could buy regular slabs and plant 2 trees in it.

kaka420 said:

grodan has mini slabs you can now buy for about $6, one is perfect for under a 6" or you could buy regular slabs and plant 2 trees in it.

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Think I'll need it? Im about to switch to flower. Im only hesitant because ive seen people stop at the 6" and finished from there. Maybe I veg too long.. Over 2 months now.

JDMase said:

Think I'll need it? Im about to switch to flower. Im only hesitant because ive seen people stop at the 6" and finished from there. Maybe I veg too long.. Over 2 months now.

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I would, it will provide more access to moisture as the plant starts budding. You could flower in a 6" but I personally would give it a little more... be it more rockwool, adding grow rocks to your tray, small cubes, etc.

I use 1 cubic inch blocks per seedling, then transfer to DWC, netpots half full with clay pebbles. Insert the rockwhool, then fill the rest of the way with clay pebbles. The rockwhool remains in place the whole grow, no problems from what I can tell even when I accidently spill water down the netpot when topping off.