It's important to not imagine that the category can replace information in the biography. A category can only supplement what's in the biography, it cannot replace it, because categories by themselves are unsourced information. It's only in the biography that the profiler can state where the information came from, that the person was an avid gardener.
That then begs the second question: once you have stated in the biography that the person was an avid gardener, and shown the source for this information, what additional genealogical purpose is served by grouping the person with other avid gardeners via a category?