Do you know what kind of jasminum? It may be too much fertilizer, they don't need much. Or it could be the plants are losing vigour through the repotting -- do you put them into larger pots or trim the roots and put 'em back in the same size? Do they receive the same light and watering schedule? Are the leaves and stems still the same, or have they changed as well?

Jim

Jasminum Angulare. I re-pot them every year early spring in larger pots. I have no problem with the plant as such. They look healthy and all leaves are bright. I do use fertilizer-miracle grow sticks. They get water and sun at scheduled time. New stems have appeared with new leaves and naturally old leaves has fallen off. I do get may flowers but small size.