ides , ▁R . ▁pra ec ox ▁and ▁R . ▁w ard ii . ▁ ▁Distribution ▁and ▁habitat ▁ ▁Ros co ea ▁h ume ana ▁occurs ▁in ▁a ▁variety ▁of ▁habit ats , ▁such ▁as ▁p ine ▁for ests , ▁scr ub , ▁me adows , ▁grass y ▁and ▁rock y ▁areas , ▁and ▁lim estone ▁cl iffs , ▁between ▁ 2 , 9 0 0 ▁and ▁ 3 , 8 0 0 ▁metres ▁in ▁the ▁S ich uan ▁and ▁Y unn an ▁provinces ▁of ▁China . ▁ ▁Cult iv ation ▁ ▁Some ▁Ros co ea ▁species ▁and ▁cultiv ars , ▁including ▁R . ▁h ume ana , ▁are ▁grown ▁in ▁rock ▁gard ens . ▁They ▁generally ▁require ▁a ▁relatively ▁sun ny ▁position ▁with ▁mo ist ure - ret aining ▁but ▁well - dra ined ▁soil . ▁As ▁they ▁do ▁not ▁appear ▁above ▁ground ▁until ▁late ▁spring ▁or ▁even ▁early ▁summer , ▁they ▁escape ▁fro st ▁damage ▁in ▁regions ▁where ▁sub zero ▁temper atures ▁occur . ▁R . ▁h ume ana ▁was ▁described ▁in ▁ 1 9 9 9 ▁as ▁" one ▁of ▁the ▁more ▁popular ▁species " ▁that ▁had ▁been ▁cultiv ated ▁for ▁many ▁years . ▁When ▁grown ▁at ▁Royal ▁Botan ic ▁Gard ens , ▁K ew , ▁it ▁flowers ▁in ▁May ▁and ▁June ▁before ▁the ▁leaves ▁have ▁fully ▁expanded . ▁When ▁they ▁have , ▁after ▁flow ering , ▁this ▁is ▁one ▁of ▁the ▁largest ▁species ▁of ▁the ▁genus ▁in ▁cultiv ation . ▁It ▁pre fers ▁some ▁sh ade . ▁ ▁R