[JayG]

Is paint brush pollination needed in a greenhouse?

Not for aubergines, peppers, chillies or tomatoes - they are very efficient self-pollinators, but a little shake of the stems from time to time helps to distribute the pollen within the flowers so you get the best possible set.

Many GH cukes are all female varieties these days so don't need pollinating, but those that do would probably benefit from the paintbrush treatment. Check the packet or online if you're not sure.