I bought some Impatiens from a nursery.
after they grew i took some cuttings and sowed some seeds.
There are not very large yet but still, even now they look like they are developing very differently from the ones that i got from the nursery.

The Impatiens plants from the nursery has about 4-6 stems that comes out of the ground and they are all one plant, not just one stem branched but more like a bush, roots that produced several stems.

The Ones i make from cuttings and seeds has just one stem.
This stem did not branched yet, but even so , it looks like it is going to get branched above ground and relatively high on the stem (even if i will pinch it at the top).
meaning it looks like it is going to get branched but not add more stems.
when the nursery plants are branched very low on the stem, and has several stems that come out of the ground just a bit spaced from one other.

how to they do that?
how do the nurseries produce small plants which has several stems?

Is this just a matter of time?
or
do they take cuttings and stick a well branched part of the plant covered in the soil in a way that few stems are covered with soil?