All geraniums can be grown from stem cuttings although some varieties are easier to propagate than others. Cuttings can be taken any time of the year in areas where the climate is mild. Cuttings should be taken when plants are vegetative and not when they are in full bloom.
Take cuttings from a healthy plant free of disease and pests. Use a hand pruner or sharp knife and remove a 4 to 6 inch long cutting from the tip of the stem. Make a straight cut across the stem just below a node (the swollen area on the stem where leaves are attached to the stem). If you take cuttings from more than one plant disinfect your shears after each plant with a solution of equal parts of rubbing alcohol and water.
Remove all leaves from the bottom half of each cutting and stick the cuttings in a small clean container filled with new potting soil. To provide better drainage use equal parts potting soil and perlite. Cuttings can be planted immediately and do not have to be treated with a rooting hormone or fungicide. Plant several cuttings in the container, then water until the potting mix is thoroughly wet. Place the container in an area that receives bright light but not direct sun. Water when the surface of the soil is slightly dry. Do not cover the cuttings with a plastic bag since this can promote decay. When cuttings are well rooted, transplant them to a larger container or to the garden and provide mid-day shade for about two weeks.
If you prefer to plant cuttings directly in the garden first place them in a cool and dry location for 1-3 days until callous tissue forms on the cut surface. This will help protect the cutting from decay. Plant cuttings in well-drained soil and give them some shade. Water well after planting, then only water when the soil begins to dry.
By V. Lazaneo, Urban Horticulture Advisor, Emeritus, UC Cooperative Extension, August 2012