As palms can take quite a few years to form their trunks, at first they will take up more space than they need later on. Therefore, if planted in streets, enough leaves should be either tied up or cut, in order not to obstruct or endanger people or vehicles passing by.
When bordering roads and avenues, they should be spaced according to their kind. Sometimes a good effect can be obtained by placing them close to eachother, so that their foliage can intermingle, or on the other hand, by separating them sufficiently to avoid entwinement (Jubaea chilensis among others)
It goes without saying that in choosing a palm one has to take into account the height to which it will eventually grow. Small gardens need small species, such as Phoenix roebelinii, leaving the larger kinds of palms for where there is space for them to grow. The proportions, the scale and the volume of the trees must always come first when making a decision.