stems/stakes are long enough so they go down deep. I would make sure they go down into the ground by at least a foot. I don't like to affix anything into the ground permanently because I have winter here and I don't want them to leave them out in the elements. Also, I don't use any items that I cherish too much in case there's a freak storm or something, and if you're worried about wind place them in areas you know are protected. It's very windy here,and mine were fine last year until I took them in for the winter, but every location is different. I hope this helps!!Tuula :)