Are plants in small SQUARE pots more vulnerable?

I grew some wall flowers from seed in the Autumn. I had to leave them in pots. I could not get them in the ground due to unforseen circumstances.
Most of them in the small square pots have died, but most of those in small round pots are ok.
Anyone know why this could be?
0
Posts
I don’t think sowing wallflower seeds in the autumn is the correct time, sow them in April, then keep potting on until you have a decent size plant to plant out in October ready for the following Spring flowering.
I always use square pots, they fit in trays better and the roots don’t go round and round in circles like they do in round pots.