Clay pebbles/flood and drain

jollyboy

Well-Known Member
So I've got a couple of plants growing in rock wool that are ready to go into clay pebbles, plenty of roots showing. Problem is, they're going into my mates iws system and he's not ready for them yet. Still has some finishing, about 2 weeks off.

If I get some pots off him and fill with pebbles how often would they need watering to keep them going?

Has anyone hand watered pebbles before? How long will they stay wet? Or should I just keep them in the rockwool another couple of weeks?

They're currently doing well but worried the root system will start to suffer soon.
 

whitey78

Well-Known Member
It's all plant dependent man... put the cubes into the pebbles and start out hand watering 2-3 times a day during lights on... I'd say 2 minimum to start... about an hour after the lights come on, and then if you wanted to get technical check back every hour till you see the plants start wilting like they need a watering, count the hours it took and there you go... they'll need watering every x amount of hours during lights on... I don't use rockwool cubes so I don't know but just using hydroton I flood my tables 6 times a day/every 2 hours during lights on but that would be too much if I was using rockwool cubes...
 

jollyboy

Well-Known Member
Ok guys so another question for you, I've tried to search on Google but can't find an answer.

I've manually flooded for a while now and they're doing fine, all good, roots are establishing in the clay pebbles and they're nice and healthy.

We've just put them into the iws system and when it floods the water reaches the bottom of the rockwool, effect of this is that the rockwool wicks and saturates.

Once drained the clay pebbles seem to dry out much quicker than the rockwool. Will this cause root problems in the future? The rockwool seems like it would stay wet for a couple of days so will never properly dry out between cycles.

It was never a problem in my old nft system so maybe I'm over thinking it a bit!
 

whitey78

Well-Known Member
If your flooding up to the rw cube your good, more watering is better with hydroton (which is why I don't use rockwool cubes) but even though they don't look like it; the clay pebbles do hold some moisture.... I use no other medium aside from gro-stones which are similar as far as water retention properties... but aero clones from the cloner into the gro stones/hydroton (very carefully) and it allows me to flood/oxygenate the root zone more often without any worry of over watering... also not using cubes saves me one more expense/thing to get rid of after a plant cycle...

I've actually accidentally left my pumps on over night once so they flooded for 12 hours straight and the plants didn't seem to be bothered by it.. I canceled the first 2 waterings of the lights on day but other than that they're fine... I think had I been using rw cubes I'd be in trouble from that mishap..

There's nothing wrong with using cubes, it may benefit your situation... I just choose not to... Aero cloning works better for me...

I only flood my table during lights on so my girls go 12, almost 13 hours without being watered in just hydroton (and some "grow stones" which i mix in 1 bag of it to 2 bags of hydro-corn...) seeing i wait another 45-60 minutes after lights on before the first flood of the day is set to start so I really wouldn't worry about under watering at all, but over watering can be a problem for u....

Maybe look into since your girls are all rooted nice, should u actually be watering up to the cube or what... Honestly I really don't know....
 
Last edited:

jollyboy

Well-Known Member
Cheers Whitey, good info, I saw a guide on a hydro store website that said you should flood upto the bottom 1/3 not over the bottom 1/3 to prevent them getting too saturated. Like I say though the RW wicks and saturates anyway.

Think it'll be fine to be honest. In nft the RW is constantly saturated with no ill effects unless the roots don't take to the spreader matt. Think this will be the same and they taking to the clay very well.

Like the system so far and looking forward to seeing it progress. Tray systems seem the way forward from what I can see at the moment (this one has pots) and aero clones would be perfect although my plants were from seed this time so I guess I would need RW or similar for germination anyway.

Thanks again for the info.
 

HydoDan

Well-Known Member
Ok guys so another question for you, I've tried to search on Google but can't find an answer.

I've manually flooded for a while now and they're doing fine, all good, roots are establishing in the clay pebbles and they're nice and healthy.

We've just put them into the iws system and when it floods the water reaches the bottom of the rockwool, effect of this is that the rockwool wicks and saturates.


Once drained the clay pebbles seem to dry out much quicker than the rockwool. Will this cause root problems in the future? The rockwool seems like it would stay wet for a couple of days so will never properly dry out between cycles.

It was never a problem in my old nft system so maybe I'm over thinking it a bit!
I have had this problem with rockwool... It stayed too wet and rotted right at the root crown..
Lost a nice kandy kush.. can you keep it from getting wet?
 

Budley Doright

Well-Known Member
I run suspended pots with clones in root riot cubes and RW (prefer the cubes) and once roots are established I lower my flood level to just below (1cm) and flood every couple of hours but have also done the continuos flood and they both work. The key I have notice, for me, is wait till the roots are established then flood times seem way less critical.
 

jollyboy

Well-Known Member
I have had this problem with rockwool... It stayed too wet and rotted right at the root crown..
Lost a nice kandy kush.. can you keep it from getting wet?
So yours rotted? That's not good. I've used Nft plenty, the rockwool is always wet in nft but it doesn't rot, thought it would be the same.

Anyone else used rockwool + clay. Must be a common combination in a flood and drain system?
 

CannabisNerd

Well-Known Member
Once you have enough roots established in the hydroton lower the flood level to barely touching the rw or below it. The rw is just to start the cuttings, it doesn't have to stay wet after the roots are established into their final destination. It could cause issues if the rw stays too wet, but usually doesn't but if you have enough roots below the rw, the rw will just be woody roots and a stem eventually.
 

jollyboy

Well-Known Member
Once you have enough roots established in the hydroton lower the flood level to barely touching the rw or below it. The rw is just to start the cuttings, it doesn't have to stay wet after the roots are established into their final destination. It could cause issues if the rw stays too wet, but usually doesn't but if you have enough roots below the rw, the rw will just be woody roots and a stem eventually.
Perfect, thanks CN, makes sense.
 

PetFlora

Well-Known Member
Pebbles are a PITA. I switched to ornamental stones, available at Dollar Stores, and possibly in bulk bags at a Nursery. They do ot break down like pebbles, they are easy to remove from the roots when finished, easy to clean and reuse

IMG_2137.JPG
 

PetFlora

Well-Known Member
Roots enjoy a near dry period, which encourages them to grow in search of. In veg I flood every hour, then extend to every 3-4 hours
 
Top