When our Oleander died of old age we decided to try a different "indoor shrub" and started four Abutilon from seed. They are now a foot high in 5" pots in a south window. Wondering why they can't take full sun for several hours but do OK if we lower the venetian and partially open slats. We have decided to raise two as standards and two as multi stemmed. When do we nip the latter. How often fertilized ? Better in east window?
You can feed them once a month with a standard house plant food. If they don't like the full southern exposure maybe an east window is better, but I think they will need bright conditions to flower well. As to pruning for a multi-stemmed plant, I think that depends on how tall you want the plant to be. If you want to keep it shorter, prune right away. I am no expert on this one, but mine always seemed to respond well to pruning and were easy to grow - some varieties are almost always in bloom.