Pointers from the experts Try a live evergreen tree for Christmas. Remember that outside plants should not be brought directly inside as the temperature change will adversely affect them. Ensure that the tree has sufficient water, try to position near a cool window, and do not leave indoors for anymore than four days. For a great smelling decoration, bring in fresh evergreen or holly trimmings to make boughs. Split or mash stems and store in water until you need them. You can also fill a bowl with collected pinecones.