WordNet sense 1 (intellectually productive):

prolific

WordNet sense 2 (producing or capable of producing (especially abundantly)):

productive

WordNet sense 3 (marked by great fruitfulness):

fat, rich

WordNet sense 4 (productive or conducive to producing in abundance):

fruitful

WordNet sense 5 (very fertile; producing profuse growth):

rank

WordNet sense 6 (capable of producing offspring or vegetation):

fecund