Rooting jasmine plants in a clear glass jar filled with water allows you to watch the new roots form, a project that can be fun for children and plant lovers alike. In general, propagation success is lower in water than in a sterile soil mixture. Jasmine is one of the easier plants to root, making success more likely than with other shrubs and vines.
Fill a clear glass jar one-half to two-thirds full with clean water. The jar should hold at least 570 ml (1 pint).
Cut a branch from a healthy vigorous jasmine plant in spring or early summer. Select green wood from the current season's growth.
Cut the branch into a 15-cm (6-inch) section. Make the bottom cut at a 45-degree angle and the top cut straight across. Make the bottom cut just below a leaf node and the top cut just above a leaf node.
Remove all but two to three leaves from the top of the cutting. Roll the bottom 5 cm (2 inches) of the cutting in hormone rooting gel.
Place the cutting into the jar and put the jar in a sunny windowsill. Replace the water in the jar weekly with clean fresh water.
Leave the cutting in the jar until it has developed a root system that extends at least 5 cm (2 inches) from the cutting.
Given the failure rate of this method of propagation, starting several cuttings will improve the chances of success.