Seedlings in straight Canna CoCo -- Stunted growth?

I recently put some Seedsman White Widow Fem. seeds into 1 gallon pots of straight canna coco. They are under a 200watt blue spectrum CFL. To date, i have not used ANY additives other than bottled water (i buy it in those huge blue jugs because the chlorine in my tap water would strip paint, I swear) These are about day 19-20, WAYY behind on the growth schedule, and seem to have there growth stunted/yellowing. Ive had this problem with seedlings in coco before and never resolved the issue, and I am considering going back to Schultz soil which is worked wonders in the past-- a student in debt cannot afford to loose seedlings every 2 weeks to coco, a huge step back in the grow process.

Here are the pics.

Any idea what is causing this? I mean theres been NO and i repeat NO additives other than water at this point. Im confused. Ive noticed other ppl with similar problems but the issue never quite gets resolved(or no one seems to know what step they took to resolve it)

I did some further reasearch and noted that SALTS can be a problem in straight coco which are naturally present in the coco husk.

However, Canna Cocos website states that during the manufacturing process that have developed a way to pre-wash out most of the salts that are present....so this SHOULDNT be a problem.

would maybe adding a *little* bit of nutes be worth a try?

I use Canna Coco as my medium and have been told to nute the day it pops above ground. I fed my seedlings 25% of the recommended dosage off of Canna's Grow Guide (their nute calc).

Here is a pic from day 21 under a 150w MH @ 6700k.

Wow those babies are beautiful! Coco definitely seems to be working for you so far. I will try the quarter/fifth strength nute regimen to see how it works. Have you ever had a yellowing problem?

I'm in flowering now and combating a yellowing problem. It's either too much N and I'm burning (probably).. but everyone says not enough N... soooo I'm doing an experiment with 2 plants right now.

aquanaut said:

I use Canna Coco as my medium and have been told to nute the day it pops above ground. I fed my seedlings 25% of the recommended dosage off of Canna's Grow Guide (their nute calc).

Here is a pic from day 21 under a 150w MH @ 6700k.

Click to expand...

Wow, these look almost identical to my current Coco grows that are vegging. Right off the bat iv'e noticed that they grow much quicker and greener. I give them a low, steady dose of 3 part with a higher dose of N every 3rd feeding or so and they love it! I agree that with coco, you can give your seedlings a VERY light dose of nutes. The ones I started in Straight coco came out lime green to start and then I gave em some food and they are a nice dark, lush green now Go Coco!

aquanaut said:

I'm in flowering now and combating a yellowing problem. It's either too much N and I'm burning (probably).. but everyone says not enough N... soooo I'm doing an experiment with 2 plants right now.

Click to expand...

same boat here as well. From looking at what UB's been saying about the importance of N, I'm picking up some 30-10-10 today and will be using it with my current veg. Thought I used too much N with my plants that are currently in flower but I was wrong. The first stretch in flowering requires alot of energy and I didn't give them near enough of what they needed. Even the plant that I purposely gave more N then the others is starting to yellow, I think the key is getting the N levels up BEFORE going into flower so they start off a nice dark, lush green color. We'll see what happens this time around...

Check your pH... mine was out of wack.. somewhere north of 6.5 (stoopid color matching). I think it was a nute lock out so I adjusted to 5.8~ (again color match) and we'll see how it goes.