Are you mixing the Alfalfa pellets into the soil? Or just putting on top? I used bonemeal this year when I potted everything up too. but I don't think I've had growth like you have, Mr. Green Thumb Gabe...
Joan, deeper is better than shallow. If you're keeping them in pots, I wouldn't use garden soil, but bagged potting mix. You want to have good drainage. I find most commercial mixes that I buy at the nurseries I frequent are fine. Some folks here add perlite to get even sharper drainage.
If the roots are tangled, at the very least, loosen them up. Personally, I would untangle them and set them more or less on a straighter path. I've dug up roots over a foot deep in the garden, so keep that in mind when looking for a pot.
