Auk wrote: Depending on your goal at least a couple of years before you can start pruning.

Auk is being optimistic.
If your seedling is a pine, a juniper, any slow growing tree in general, it could take 5 years to begin serious training, and 10 years to have a decent bonsai.
I suggest you buy some older trees to have fun meanwhile.

Clicio wrote:

Auk wrote: Depending on your goal at least a couple of years before you can start pruning.

Auk is being optimistic.
If your seedling is a pine, a juniper, any slow growing tree in general, it could take 5 years to begin serious training,

I understood it is a wisteria - and I did not say you can start serious training after a couple of years.

and 10 years to have a decent bonsai..

Now you are being optimistic