Sadley its teh one thats growing the best. I topped it 2 weeks ago and the new growth is coming in with the same purple taint that yours has. it is in the stem a little but mainly right where new growth is coming out. I've read that it's from the plant "locking" the phosphorus out due to cold temps. i live in ohio and we recently had temps drop to the mid to upper 40s at night and I think it affected my plant. Hopefully its not permanent. any suggestions?