Stunted soil growth - any ideas?

[ipchains]

Hi all,

Recently I've started soil growth with several strains and encountered stunted growth problem. Setup in details:

Light - Mix of 2700K and 6500K 50w led arrays (about 50w per sq./f)
Soil - standard flower shop soil
Nutrients - Atlantica Agricola Raikat series (root, grow, bloom)
Strains - AK47, White Widow
Growth - germinated from seeds

Ladies on photos are about 4 weeks old (seem VERY stunted to me) and about 6-7 days ago I've noticed brown spots on lower leaves. It seems that these spots are progressing and increasing in size eventually leading to leaf death. Seem like phosphorus deficiency to me. Since I can not alter PH level of soil mix much, I've been thinking about foliar feeding. Do you think this can be an option?

Please, share your opinion regarding problem cause and how can it be resolved. Many thanks in advance!

 

[ssq.talker]

no pictures...

 

[ipchains]

Album was set to private - changed to public. Should be visible now...

 

[atk7]

Is there good drainage? Almost looks like the roots are drowning

 

[DJXX]

i think you need some perlite in there...air is one of the best things you can give to babies...i think the roots need some breathing room.. DJXX

 

[ipchains]

atk7, it takes like 1-.5 minutes from watering to run-off. Tested bottom of the pots - no signs of excessive water

 

[ipchains]

DJXX, Can perlite be added at this stage? I though that when root system was developed you may not alter soil...

 

[Elements001]

What have you been feeding them at, ppm/ec wise? They look very very underfed to me. I had the same thing happen when i started out in coco. If there aren't enough ferts in your soil your gonna need to start supplementing them.

I use General Hydroponics FloraNova veg. It's a 1 part formula that works really well, especially for beginners imo.

This is what mine looked like when I was underfeeding them

Once I figured out I was under feeding I bought the GH Floranova and after maybe a week she looked like this.

If your like me you probably did a lot of reading, and one of the most common mistakes is over feeding. In trying to be proactive I kept the feed very low, next to none actually. I thought the original nutes I was using had enough, or that my medium had enough ferts since it said all this guano and worm casting stuff on the bag. That and I figured they were so young, they couldnt possibly need feed yet. Depending on the medium you can start using ferts almost immeadiately without burning the girls when mixed in the proper ppm and pH.


Big thanks to papaduc for helping me out on this one, he saved my girl!

 

[ipchains]

Elements001, Seems quite similar to me as well. Currently I'm feeding 1/3 strength recommended by manufacturer (to avoid plant burn) . will try full strength on next watering schedule.
I think perhaps there can be both problems simultaneously - underfeeding + bad drainage to make things even worse

Guys, Many thanks for your help. Just 1 more question - How can I improve drainage (aka add perlite) at this stage not damaging plant roots and avoid further stress to plants?

 

[ipchains]

No worries, perhaps I'll just repot them... Thank you all again!