Experiment Update
 

I think the photo says it all. Plant A seems to be growing faster than plant B. I did some minor photoshopping of the photos to remove distracting things from the background and to scale them properly.

I'm still going to continue the current protocol until I run out of fertilizer, which could be a while--I mixed a gallon of each one. After that, I'll move on to the next plan, which will be controlled N concentration, different brand, as per Ray's suggestion.

Interesting results so far - keep us posted.

Plant A is showing some excellent liking to its conditions and regimen.

I'm with Cheryl.

I'm not jumping to conclusions yet. The growth of plant A is more than that of B, but A was a bigger plant to start out with, and teh differences are small. I've still got about 3 quarts of fert for each mixed up...after I run out, I'll move on to the next trial, and I'll have the wifey tell me which was which.

Took my weekly measurements today. Both plants grew, but plant A added more. it added about 5 mm of leaf span this week, whereas plant B added only 1.

I still have a little more than half a gallon of each fertilizer...

More weekly measurements. Plant B put on 4 mm of leaf span and 4 mm of longest leaf, whereas plant A only put on 2 mm of longest leaf. So maybe plant B was just a slow starter?

:scratchhead: :hmm

An interesting experiment.....You never know if it's due to the difference in conditions or if one plant is just more vigorous than the other...:scratchhead:

Well if I were going to do this right, I would get a flask or two of something and then randomize which plantlets were in each group. But alas, this is a much smaller scale version. I've been reading on slippertalk that the plants from a flask can show huge variability in growth rates (up to 50% after several years), so certainly it's hard to say how much is attributable to conditions vs intrinsic factors.

Anyway, it's still way too early to draw any conclusions. Further results to follow.

That's always been my experience with growing plants from flask. There are always a few that are very vigorous, most are just average and some don't seem to grow at all. I have some phrag seedlings that were very quick and developed several growths, bloomed several times while their siblings haven't bloomed yet.
Often, the fast growers bloom very well and there is a direct correlation between plant vigor and flower quality.