Answer: Forsythias root readily from cuttings. In early spring, stem cuttings will root directly in soil with or without the help of rooting hormone. They will also root in water, but in my experience the soil-rooted cuttings transplant better.
Later in the season another simple way is to "layer" branches by bending a branch tip down to the ground, wounding the bark lightly where it touches the soil and burying that point with good soil. Set a rock on top if need be to keep it bent (Leave the tip exposed to light) and check periodically for roots. Once roots have formed you can separate the "plantlet" from the mother plant and move it to it's own location. Spring is a good time to transplant these.
Good luck with your forsythias!
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