Seeds for hydro grow

[Geeza]

Hi guys,
I do an indoor DWC same as Sirius, I normally do cuttings in rockwool and that’s not been an issue for me,but recently I bought some seeds and getting them going in rock-wool is causing me grief, (paper towel in plates method till they sprout then into the rock wool cubes) they struggle to get going, and even when they do come out with the first set of leaves they just seem to stop, I’ve tried to give them a quarter strength nute mix and still I can’t seem to get them to show roots and they end up dying, it’s cost me a small fortune and a shitload of time wasted.
Can anyone please tell me what other options there are?
as I have now read that rock wool is very harmful for not only the environment but to your health as well, I’m also told that jiffy’s/peat are unsuitable for hydro,
thanks to you all in advance.

[Rwise]

How are you prepping the RW?

Rockwool has a naturally high pH, typically around 8.0.
Starting seeds can sometimes be a stressful adventure. It’s a constant balance between keeping them wet enough to promote germination without having them so wet they dampen off and die. Rockwool cubes are popular for germinating seeds in because of their excellent moisture retention — they are great at helping to keep seeds or seedlings from drying out but don’t let them sit in a waterlogged environment.

[Geeza]

Hi Rwise,
Thanks for your input, I think you could be on to it, the moisture thing may be my issue, it sure is tricky to get that right, I suspect now that I could be overdoing it and waterlogging them, as I worry they may dry out,
I will go easier on this lot and keep a closer eye on them and see how they go,
If they come through, would the light mix (700-800EC) of nutes I dose them suffice?

[Rwise]

I do not use this method, I grow in soil outside so I cannot answer that question.

[Bluey]

I would go half the EC for seeds trying to root. EC 0.4 till first set if leaves

[Geeza]

I was told by my local grow shop that I should rinse the rock wool with water ph’d at 5-5.5 and then should be good to go, I have done this, however, like I said, I may have them germinate and come through with the first set of real leaves and while waiting for roots to exit the cube (which are approx 3cm square) they just seem to stop growing?? I’m starting to wonder if maybe I’m not getting the balance of moisture/oxygen right?
I understand that they’re best kept warm-ish (21-28 degrees Celsius) so I try to maintain that without allowing them to dry out, but just don’t seem to have any success, extremely costly and frustrating😬😬😬😬

[Bluey]

Keep temps on the lower side of that range.

What EC & pH are you giving them on the first few feeds once in the RW?

I hate this stage myself. It does my head in waiting waiting waiting

[Geeza]

Hi Bluey,
I try to get the EC between 600-800 and PH 5-5.9,
I have a feeling I could be waterlogging them, as I usually worry I could dry them out, but hey, I guess that's just as detrimental as waterlogging
I will keep a closer eye on this lot and see how they go
Thanks for your input,

[Bluey]

Well I do a aerponics bucket but DWC is a bit different. Maybe read up on frequency and timings also of fertigation.

I think target starting pH is 5.8 and let it climb above a bit. 5 is way too low. Start 5.8

0.4 EC till first set of leaves or two. 0.8 when it leaves seedling stage..so a few mature nodes at least