I have several species. I kept them in the greenhouse all winter, but they
never fully went dormant. Now, I find their foliage is not all that vigorous.
Could it be they needed a dormant period? If so, how can I encourage dormancy in
a greenhouse which is actually a cool house since very little heat to prevent
frost is used.

These plants have flowered, but not in the vigorous way they have in the past.
they are in huge 30 -40 gallon containers, are fed regularly, foliarly sprayed
with seaweed, and get drenched with compost leachate (tea) about every two
weeks. I don't see disease, just the lack of foliage vigor and flowering
decline.

Victoria