Actually this idea works also very good for putting up the christmas tree. We do not use a plastic flower pot but an 25 litre zinc tub (our tree is at least 2 metre so you need some contra-weight). At the place you want the tree you add the tree to the tub first and fill up with cobble stones (or any other stone of course, as long as it fits between tree trunk and tub). After that there is no way a cat, child or dog will topple the tree. You can even add water to the tub. In case the tub is visible you can camouflage with a christmas cloth.
Ruud
