When learning how to propagate hydrangeas, many gardeners prefer taking softwood cuttings during the active growing season because young stems can root relatively easily. Select a healthy stem that is not flowering and make a clean cutting below a leaf node. Remove the lower leaves and place the cutting in a moist, well-draining medium. Keep the container in bright, indirect light and maintain steady moisture. Avoid excessive watering, as overly wet conditions can cause the cutting to rot. Once roots and new growth develop, gradually move the young plant to its growing location.