Rockwool watering frequency

J. Rocket said:

white cubes are called "pargro quick drain". still a grodan product.
from my use of the 6x I'd say a slightly better moisture gradient/draining but still holds about a half gallon soaked.
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Your plants haven’t grown in months

bk78 said:

Your plants haven’t grown in months

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sure they have.
you just gotta believe!

trademanny said:

Should I be waiting until a similar dryback (20-30) between each irrigation, or is that only for when first establishing the block and fully saturating it?

Thank you for the help!

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I let it dry back some every time. It becomes more as the block fills with roots and uses water more rapidly.

J. Rocket said:

I let it dry back some every time. It becomes more as the block fills with roots and uses water more rapidly.

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How do you judge the dryback? Weighing blocks works for now, but it's not something that's feasible longer term.

J. Rocket said:

I let it dry back some every time. It becomes more as the block fills with roots and uses water more rapidly.

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Ok, I'm debating posting this as a new thread as the topic is shifting a bit, but can you (or anyone else) check my math on this?

I apologize for the brain dump, but I want to be sure whoever is helping me has all the context here.

These clones were rooted in 1.5" gro-blocks and then put into newly saturated 6" hugos once I saw some roots popping through the bottom. Since then (2 weeks), I waited for the weight of the blocks to dry back 20-30% before irrigating again. This took about a week or so, and I gave them each about 500ml and there was plenty of runoff.

Since then, starting yesterday I've given them a couple of 100ml shots as I'm learning a little more about dryback. I've ready so many horror stories about rockwool and overwatering, too wet, etc, etc, but it's hard to discern what the 'right' way to go here, is. I've read Grodan's docs, but I'm not going to buy a Grosens system for my personal little closet grow.

I'm worried about overwatering, but I fear I may be suffocating them by not watering enough as the plants are depleting the dissolved oxygen in the water already in the cube.

So.. on one hand, I'm worried about this dryback concept, but on the other hand, it'll take days for my blocks to dry back that far. Furthermore, if I _do_ have pH or nutrient issues, I can't be waiting for this dryback to correct them.

Am I overthinking the dryback? Is that really only necessary for turbo-charged growth? I mean, I've grown in DWC before where the roots live in water, so clearly it's not 'dry' that they need.

I want to be sure I have a handle on this and fully understand everything before I put my drippers in and turn on the automation.

once roots are coming out the bottom of the block I go a couple days between watering to run-off.
another week of growth and they get a daily lights on auto feed.
its tough to overwater once they get rippin. I think you can water too often though.
if you have to do something because you think you overwatered,
just fold a small towel and put it under the block.
watch it wick the solution out.
another option if you are comfortable picking up the block.
gently hold it with one lower corner down.
I've drained around 300ml from a soaked block that wasnt running off sitting flat.