Probably not enough water for both parts. They're an understorey plant, in woodland that receives a fair bit of rain, so it may be that it requires more of the wet stuff. Is it in a pot? Phil J

Thanks for all the answers,the plant is in the ground,shade half the day,and gets about 5ltrs water a day,only been planted since may from garden center, its about 24" high and 9" in diam,I have a feeling it might have been left over from last years stock ?