It is very important that you find out beforehand how tall you want the garden trellis to be. Having a trellis which is too tall can cause problems with the neighbors, but can also be much larger than you initially intended. Similarly, a garden trellis which is too low might not be as effective as you had hoped – for example, it may not provide a lot of privacy. Before you go shopping for your tall garden trellis, measure the areas of your garden where you intend to position them. It is also a good idea to go inside your house and imagine the view of your garden once you have installed the trellis in the desired area.