Q.Garden plant repotted from the earth soil to a plant pot
Hi! When I was a child my dad planted a perennial which produced large flowers. My brother took a bulb out and planted it into normal compost without John Innes last October. We were not sure it would show itself this spring, but it has. Unfortunately , many weeds grew in the pot before this happened. I have brought it home with me now and removed the weeds ,but there are many weed roots in the compost.
Q1 Can I repot it while it is growing or shall I wait until October.
Q2 Shall I use Compost with John Innes?

I'm not clear on the type of bulb you are growing.
I would recommend waiting until the bulb is done flowering and the leaves have died back to remove a bulb and repot.
Do the best you can by gently weeding the pot.
This will allow the bulb to finish it's growing cycle, undisturbed.
John Innes is available in different types, choose the material for an established planting.