I have that same thing these days.
I think it is my soil.
What I used a while back was bought out,then the Co. failed/out of biz.
Tried the Ednas Best - It sucks for My grow!
http://www.ebstone.org/products/eb-stone-organics
Too many bills to pay,I only can scratch up a few $ here and there for a pot or so of soil.
Tried Edna's best last year.
It was the cheapest soil.
To top off my pots.
It sucks for My Grow.
Too wet or too dry,Even moist it shrinks up in my pots.Making water run off...
Maybe a PH thing-Nutes.
I like my version of 5-1-1.
Actually 3-1-1 is what I mixed.
Old 5-1-1 mixed with new stuff.
Most of my garden is total Southern Exposure.
Gotta add more Peat or broken down 5-1-1 to hold water...
I like 5-1-1 after a season or 2.
For Southern exposure in my garden (100 degree summers),works great.
The stuff that breaks down after a season or 2 holds the moisture and the bark turns into a slow release nute.
As long as I re mix my old soil to top off pots when I give my plants away.
My current starts ,in Ednas are looking like your pics.
I'll put my starts out early just to try and keep them alive.
In outside soil-what I used over the years.
I have no problem outside,years of the bark soil out there.
I used the crap stuff only because I had to at the time...
Also,Orchid bark was what I used for my 5-1-1.
I've found small/fine colored decorative bark is a lot better,and Way cheaper.
The same amount is diferent,allows more air space for the roots-I think.
http://www.greenarrownurseries.com/current/
I don't remember the brand name.
They are up the street.A short walk.
If you go there.ask for Chris.
He is a very cool guy to get info from about all kinds of plants,Only thing I am better than Chris is I'm a pepper Addict. LOL
Chris knows Any plants they sell.
Plus he is a cool guy personality wise.
When I'm at Green Arrow,Chris askes me,In Front of a customer about what he knows I am informed about-Good bugs Vs. Bad,Pepper stuff etc.
Not that I'm an expert,I only know what works for My Grow.
Babbling I guess,but I am only trying to help out.
I'd bet,but don't know,but I'd think if you E mailed or more probably call him at work , a request to Chris Via Green Arrow,Chis would help you out-If he could.
He went to School to learn stuff I have from trial and error.
He knows why stuff works,I only know my grow...
Smoke
PS. I use low mixes of ferts. every time I water.
I like Alaska Fish and a Very small amount of Seaweed Extract.
Use Alaska,other fish ferts are Urea and fish.
For me they burn my plants.
Alaska doesn't.
Alaska I think builds up my soil micro stuff.
It I Think has to break down-Micro stuff in the soil or???
Has to break down before it is plant usable-I think.
It is what I like for my soil mixes-so far.
Healthy looking one 
to T.H.P. ! 
what you feeding them ? 