Answer: Your zip code places you in zone 6A or the coldest part of zone 6. Depending on your microclimate, in an exposed or windy or rural spot you might be gardening in the equivalent of zone 5. Phlomis lanata or Jerusalem sage is listed as hardy only to zone 8 in the Monrovia catalog. There are some other garden-worthy Phlomis such as P. fruticosa that are listed as hardy into zone 6. Either way, I think your climate is probably just too cold -- and the growing season too short -- for it to bloom. I'm sorry I can't be more encouraging.
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