Taz - welcome -

please read FAQs at this forum. Read info on Rachelsreflections.org - it covers ALL the basics. Pay special attention - on the long neck care (that's your tree thingie).
You are right, yes, they should be slightly rootbound, if you have 4" pots the only thing you need to do - is wash and scrub them thouroughly after you pop the rootballs out - but the correct recommendation - size of the pot = 1/3 of the leaf span. The AV soil you can buy in a store will work if you add about 1/3-1/4 perlite to it. Otherwise it is too heavy on a peat side and the roots do not breath properly.

Good Luck, do your homework - means read these materials - you will enjoy doing it - really good stuff, explanations and pics - and come back with the questions.

Irina

Thank you! One question: Is it absolutely necessary to do the root hormone spray?

African violets root pretty readily without the use of hormone powders or sprays. However, I do find they root faster if given extra humidity.

Thank you again. Humidity not an issue. Plenty of baggies around. lol