This is a fern that I absolutely LOVE. It is quite upright growing, and very vigorous, but has not spread for me at all so is certainly not invasive. I think it is wintergreen for me but I seem to have cut it back in fall in a spurt of tidiness.

Hi Karin1,

Dryopteris crassirhizoma is native to Japan and China. Common name is Thick Stem Wood Fern.

This fern would not be my first choice to grow in a Zone 5 garden. Especially in a garden that is important for viewing. Dryopteris crassirhizoma is an uncommon fern (difficult to find at greenhouses) and is unlikely to grow well in our area. I think Dryopteris marginalis is a much safer choice.

I grow about 40 different species of ferns and have studied ferns growing in many gardens throughout the Wisconsin and northern Illinois. I have not not found anyone that grew crassirhizoma well. This is not to say that it is impossible to grow here, just very very challenging. If you are an expert - go for it. If you are a novice - pick a different species.

Hope this helps.

Tom