Hi Pat, Rather than cut off the top half, you might do better to try the following. Uproot the plant and strip off all foliage except the top tuft of leaves. Dig a trench about six or eight inches deep and set the plant in it with just the top sticking out. Fill and firm in and don't worry that the tip is slanted. It will straighten up on its own if it makes it. What you will have done is cut down on the amount of foliage the roots must support. New roots will form on the entire length of the buried stem. This will work only if the plant isn't too far gone. If you cut off the top, the growth tip will be lost. Good gardening, Chuck Wyatt