Hi,
My neighbor has a small pot of these and wonders how best to care for them in our zone 6a/6b? Her pond is preformed isn't super deep and has no mud. Thanks in advance!

Does your neighbor have the cattail sitting on a shelf in the pond? If so, I would leave it there. The pond will freeze solid (and so will the plant). But no one brings mini cattails inside in their native habitat (which, I think, is Siberia).

If she is worried, she can bring it in and store it in an unheated garage or basement. Remember, though, her mini cattail will still need constant moisture.

Thank you for answering. Since there isn't any mud around them, She's decided to bury them in the ground and cover the pots with leaves

That will only work if she also keeps them wet. The plants will desicate in the cold without moisture.

Ok ---I'll tell her to keep them wet. Thank you Daisy!

Daisy, I found this article by someone that lives right near us:
http://garden.org/ideas/view/H...

I think the operative words in that article are 'above ground' - Plants kept in above ground containers need to be hardy to at least two zones below whatever your zone is. That means a plant would have to be hardy to Zone 4a in your area to be safe in a container above ground for the winter. So sinking them into the ground is a good option. I'm not sure what the difference is between "in the ground" and "in the pond that is in the ground".

The water in the ground and the water in the pond are both going to freeze solid and the temperature will be lower than 32* because of the ambient temperature of the air. But an above ground water garden or planter box will be less insulated so the plants will have to withstand colder temperatures.