Merryl, it would be good to see your location next to your name so all of us here can give you advice based on your location too. Having said that, my thoughts are that your plant is probably being kept too dry. The location in your photo looks hot and dry, I may be wrong, so please tell us what country you are in, and what season eg: Summer/Winter. If your buds are becoming brittle/dry, I would think that your plant needs more frequent watering with the sun/heat that it's getting. That would be the most likely cause of dry/brittle buds. I can see that your plant does not have many leaves on it at the moment, again making me think that your plant needs more water. Your potting medium looks like a good free draining mix, that would cope with more water. How often are you watering and what temperatures are you getting.

I see no need to prune your plant at this time, as that wouldn't fix your problem. Please also check that you have no problem with sap sucking insects eg: mealy bugs etc. Hope this helps :)