I'm posting this here to get info from folks with similar climate. I'm sure pachysandra behaves differently in other climates and soils.

Our shaded drive had some very large established pachysandra (the normal green japonica type) when we moved in. I'm taking some areas where the pachysandra hasn't spread yet and adding things like hostas. Some of these "areas" are strips maybe 4' wide between two pachysandra patches. Right now I've got some hostas in those strips.

Hostas are deceiving--on the hand, they're hard to kill, but on the other hand, without good moisture and some sun protection they won't perform "to their best." They might not be dying, but perhaps they're not exactly thriving. We've had two dry summers and my new large specimens (Empress Wu, Sum and Substance, Blue Mammoth to name three) are still on the small side, I'm assuming due to lack of moisture.

Trying to keep the pachysandra in bounds isn't as bad a chore as some other invasive groundcovers, but given the sheer amount of pachysandra I have, it's a chore. Lots and lots of linear feet of edging around these patches! I have no false barriers and maintain the borders with shovel and arm muscle.

I've been wondering about what will happen to the pachysandra if I let it grow right up to the hosta roots. I'm happy to do that, if it won't outcompete the hostas.

Online has several resources that mention both of them together, and some pictures, as well from different sites. But I don't know in those pictures and resources if they are just letting them grow near each other with some plastic boundary or manual labor keeping the roots apart. I also found one homeowner's blog that said by year three the pachysandra kill the hosta as it chokes out the hostas roots.

Do you have any experience with the roots of hosta and pachysandra mingling?