Well then. I know that plums and apricots are both deciduous plants and will lose their leaves for winter. And need much less watering during that time. I doubt that your
greenhouse window is too cold. They can take some chilling and even light frosts during winters here in SoCal.
If they are still in shot glass size containers, then yes, transplanting them now into something a bit larger is in order. At least a 4 inch pot. Beyond that there is very little need for much until they have had their winter snooze. Then feed as leaf buds swell in early
spring.