Butter Mints go stale?

Do they not have any kind of plastic packaging around them?

View Quoted Comment They do right now but when they go into the boxes, they will not.

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I would imagine that a week in advance would be okay, but if you can make time to do it later in the week, I would do it as close to the wedding as possible.

A week might be fine but if it's possible I'd try to do them slightly closer to the wedding day.

Stale might not be a problem, the mint oil may be. Since mint candies are generally flavored with an oil, it can seep and stain any porous surface (like cardboard etc). If there is no protective barrier, I would wait till as close as possible to wedding to package them.

They do get softer after so many days out. I’m not sure how long but we’ve had them become soft but the flavor is still ok