Ficus benjamina house plant 'shrub'

[Kevin_T82]

My local nursery has numerous Ficus bejamina offered as "house plant 'shrubs'" planted in 10-inch nursery pots (that look like a few individual plants per pot). All are very healthy looking, thick with foliage, dense and about 12-20-inches tall. I'm thinking of buying one and turning it into multiple pre-Bonsai. My questions are: When I go to separate them out would you:

1) Replant them into Bonsai soil?
2) 50/50 bonsai and nursery soil? Or any ratio..

A) Chop them down to start shaping after transplant?
B) Prune roots and chop?
C) Prune roots and do not chop for a few weeks?

I also have access to a commercial greenhouse with one room that is set at a continuous 65-70F and 65-100% humidity.

 

[NewWorldBonsai]

Before we begin talking about how to handle these new candidates there should be a rough goal that we're aiming at. Do you want to make them a bonsai tree asap or develop them into quality trees?

What's your location?

 

[MrFancyPlants]

I would vote for 1-C. but change "weeks" to months or maybe years.

Do you have any supplemental lighting for them? Although Ficus b. does great indoors and is a survivor, unless you can provide supplemental light, heat and humidity for them, it is really better to wait until the summer to work on them. I generally like to work on the roots and base of the tree first, since that is generally the hardest part. Once the roots are all growing in the right place, they only get better with time.
I had some pretty good luck using the tourniquet method on Ficus b. which leaves even more growing power for your tree to reach it's final design. Instead of trimming a large tap root, put a nice and thick wire around it pretty tight. The plant will slowly put out new roots all around it, but in the meantime, it can still use the root to grow.