English lavenders (such as the ‘SuperBlue’ variety) are generally winter hardy up to Zone 5—but that’s not to say that they can’t survive in colder areas if provided adequate protection. Since you cannot bury the pots, could you move them to a sheltered location such as a garden shed or garage? You’ll need to keep them insulated from the cold, since the roots won’t get the natural protection of the ground soil. Mulch over top of the plants with 3 to 4 inches of straw. Give them some water before you mulch and store them. You’ll want to make sure that they don’t dry out completely, but also that they don’t get too wet throughout the winter.
Even with all this, they may not survive the cold… Perhaps you could repot them in smaller pots and bring them inside instead?
English lavenders (such as the ‘SuperBlue’ variety) are generally winter hardy up to Zone 5—but that’s not to say that they can’t survive in colder areas if provided adequate protection. Since you cannot bury the pots, could you move them to a sheltered location such as a garden shed or garage? You’ll need to keep them insulated from the cold, since the roots won’t get the natural protection of the ground soil. Mulch over top of the plants with 3 to 4 inches of straw. Give them some water before you mulch and store them. You’ll want to make sure that they don’t dry out completely, but also that they don’t get too wet throughout the winter.
Even with all this, they may not survive the cold… Perhaps you could repot them in smaller pots and bring them inside instead?