Thanks Unity.
yes I realised afterwards that I hadnt planted some of them deep enough, also, I didn't have enough soil to fill all the pots as much as I wanted.
I think Alice is the worst affected of them all but I don't really want to replant them, at least, not until I get some more soil.
What do you think about starting with the nutes now that they are 4 weeks old? I thought I would begin with the bigger plants (the theory being they will be able to take them more than the small ones). I could argue that the smaller ones need it a bit more but, they were the worst affected with nute burn so that could be why they have not done so well. Also, the same - small plants - were all flushed, so I don't know if the flushing slowed them, the nute burn or, it could just be that they are slower developers. Everyone that I hve seen with multiple plants have some big and some small. There is another theory that the males grow quicker in order to be able to pollenate the females from above - which also makes sense.
Anyhow, I'm sticking with plan-A and introducing the nutes to the bigger ones on their next watering. Unless I am advised to do otherwise.
I have been keeping an eye on the soils' moisture and checking the weight of the plants before watering. I give them just enough to see a little seepage come through the bottom of the pots.Since I started this, they have only needed watering every 4 to 6 days. Does that sound about right?
I thought they would need watering more often but, I guess they are still babies at the moment and the pots are approximately 2 gallons.