New Grower Autos not vegging/stunted & yellow

[slant]

Indoor grower for 3 years with good yields.
Recently tried Autos and failed.
First grow
20 x Trans Siberian (Herbies seeds)
25L pots
Promix soil
Water PH 6-7
Soil PH 7

Seeds germinated in cloth and transferred straight to final
25L pots under 600W HPS dual spectrum.

17 pips hatched and grew no more than 4 inches.
Yellow/stunted. Started flowering but almost no nugs as a result of "no veg/growth" period.

Now have 10 x Kandy Kush Autos(herbies seeds)

Same scenario
2weeks in and they have stopped growing/yellow leaves afraid ill be in same situation of no veg so no nugs!

I watered with PH 6.2 yesterday to flush and today will add some bloom and grow in small quantity to see if its feed they need but seems strange as I have never fed any of my girls until they have shown signs of upward growth.

Help disillusioned by Autos after a very successful few years of regular growing.
Thanks.

 

[GCase]

Slant, we have many Promix growers. They will drop by asap. Looks like you are taking a safe approach.

Cheers and welcome.

 

[az2000]

You sound like you've grown photosensitives, have you used promix before? I'm on my 1st AF, and using promix 60%, 20% Kellog's Patio Plus potting mix, and 20% perlite. I use GH Flora series and fed 0.625-0.625-0.625 just 2-3 days after it sprouted. That's half GH's recommended seedling strength. I also sprayed Botanicare Liquid Karma a day or two after it broke soil. 2 days later I watered with 5-2.5-2.5.

Promix has virtually no nutrients. I pick up a little from the addition of Kellog potting mix. So, I can't imagine how you get by 2 weeks without feeding.

I planted directly in a 3gal pot. It seemed like it didn't grow much the first 2-3 weeks as the roots developed in that large pot. But, it eventually took off. So, part of the size problem could be similar. But, it sounds to me like lack of nutrients.

Also, I've read promix should be watered with ph 5.8 during veg, and 6.2 during flower. Since I added soil, I've been doing 6.0 and 6.2-6.3 (right now I've been doing my first flower period and experimenting with ph).

Dolomite lime (1.5 Tbsp helps stablize the ph. I use it but have no other grows to compare it to.).

 

[wwwillie]

Hey and Welcome!
Sorry to hear you are having such a rough time! They look pretty good shape and size wize, but like you said they're heading downhill.
I am too new to give any really useful advice. I was having great difficulty as well, I started to use Supercharger root tonic from Rock and I am reasonably sure it saved my grow. So much going on at the time it was hard to say, but like your lucky shorts at the ballgame, I won't grow with out it now. My pH was high too, I lowered it to 6.0 for my soil. I am not sure if any of this helps you out, I hope so.
Peace and happy growing!
Some good vibes and a double :karma Cloud: :karma Cloud: to help things along!