This question was answered previously on 05/08/25. Question # #0169834

Lavender is considered a woody herb, which can be planted in containers. Be careful about the type of lavender you choose, as not all are hardy.
https://extension.colostate.edu/topic-areas/yard-garden/growing-lavender-in-colorado-7-245/

Overwintering plants in containers requires special care:

• After several hard frosts, move them into an unheated garage or cold frame.
• If this isn't practical or you have a lot of pots to protect, make a straw bale enclosure where the pots can be placed. Cover with a couple of sturdy pieces of row crop cover (frost blanket) fabric.
• Be sure to give the pots a drink every month on a warm day so the roots don't dry out excessively.
• In spring, cut the perennials back and move them outside.

Another option: plant the lavender in a plastic container and place it inside the container during the summer months. When it's time to overwinter, plant the plastic pot in the soil in an area of your yard and mulch well and keep watered with the rest of the landscape over the winter. In the spring, remove the plastic pot from the ground and put it back into the container.

Here are a couple of links with more information: https://planttalk.colostate.edu/topics/miscellaneous/2028-overwintering-container-plants/
https://csuhort.blogspot.com/2020/11/overwintering-perennials-in-containers.html
https://plantselect.org/perennials-overwinter-above-ground/

See also this link for specifics on container planting:
https://extension.colostate.edu/docs/pubs/garden/07238.pdf

If you are a lavender fan, here's some fun information:
https://coloradolavender.org/
https://www.botanicgardens.org/events/special-events/lavender-festival