NEVER cut back Lavender, even in the Spring, when it might look like it's died. The plant rejeuvenates from the bottom of the stems (branches) up. The best way to winter over your lavender is to wait for a hard frost and the ground to freeze and then pile mulch and leaves or straw all around it (bury it in the leaves) and then uncover it in the spring and DON'T even try to prune it back!
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