Hydrangea shrubs usually grow 3 to 6 feet tall, but some grow to the size of small trees. These plants provide color from mid-July through the fall. They are cold hardy in USDA zones 4 and above, which mean they survive the winter where the temperatures do not drop below -40 degrees Fahrenheit. They grow most easily from cuttings. Knowing how to care for the cuttings will enable you to grow as many of these shrubs as you wish.
Take cuttings from a healthy hydrangea branch from April to June. For each cutting, look for a new, non-flowering shoot with two or three pairs of leaves. Measure 5 to 6 inches from the tip and cut with a sharp knife.
Fill a small pot with half peat and half perlite for every cutting. Strip the leaves from the bottom two nodes and cut the largest leaves in half. Dip the cutting bottoms in rooting hormone and stick one in each pot.
Water deeply and allow the cuttings to drain. Place a plastic bag over each cutting, keeping it from touching the leaves with small stakes. Put the cutting in a shaded area and make sure the potting medium stays moist.
Transplant the cuttings outdoors when they start growing on their own. They should root in two to three weeks at most, but some will root in only a week. Choose a shady area with moist, well-drained soil.