Question
Irish moss in pots - Is it just futile to even try this? I had a couple of pots that did spectacularly outdoors in the summer, but one died when I brought them inside and the other is looking quite feeble. It's turning brown in a lot of places and doesn't seem to be growing much. I love the plant and want to keep it in the pot, but maybe it doesn't like being potted?  Thank you for your help!

Answer
Hi Katy,
Thanx for your question.  Iris moss (Sagina subulata) is a European native growing in zones 4-9.  It is a perennial.  You need to allow it to go dormant for the winter, keeping the pots well-drained but ensuring that the soil is kept moist enough to keep the roots alive.  It is not suitable as a winter houseplant as it will eventually wear itself out and die if not allowed to go dormant.  It sounds like you had good luck with it during the regualr growing year.  Bear in mind, this plant is hardy to zone 4 which includes most of the northern tier of the Continental U.S. and Southern Canada.  You can move your pots into an unheated garage or against a wall that protects the pot from the north wind, during winter if you're worried about the plant wintering over.  I hope this helps.
Tom