You can propagate rosemary from either rosemary seeds, rosemary cuttings, or layering. I found that propagating rosemary in
water is the best way. A rooted rosemary plant from a cutting in water will mature quicker than a plant started from seed.
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A rosemary stem cutting will reach a usable size in just a few months, so you will be able to enjoy harvesting rosemary sooner, and the best of all is that the new rosemary plant you will grow from cuttings will be an exact clone of the mother plant and have the same flavor, disease resistance, and growth.
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From a single rosemary plant we can have numerous cuttings without risking the health of the plant.
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Propagating rosemary cuttings in water is very simple, you can have good success by following my Step-by-Step Instructions.
How to Propagate Rosemary in Water