I think it is going to depend on the species of oxalis. Weedy species like O. stricta or corniculata are a concern wherever they might be growing but a cultivated form - like Oxalis oregana - will be much better behaved.

depends if its a 5 foot hosta.. or a mini.. dont you think..

how about a little more specificity and perhaps a pic...

whatever they are.. it would come down to water competition.. and who would win ...

i can think of the undulatas.. and suspect nothing would defeat them... and i could think of a bunch of H i paid a hundred dollars for... and those hot house queens wouldnt last a minute with any competition..

ken

It is a cultivated form of Oxalis, though as usual, I don't know the cultivar name.

Pics or it didn't happen.

As you can see there are a variety of sizes, Smallest is a bout a foot tall and the Empress Wu is 3 feet or so.

What Hosta grows 5 feet tall! I think I want it.

I wouldn’t stress over it. It looks nice and, since it is effectively impossible to eradicate Oxalis, I’d just live with it.

Oxalis oregana is native to this area and makes a very attractive groundcover for a shady area. I have never found it to be overly aggressive or smothering of other plants. I have it growing under rhodies together with hardy cyclamen and a stoloniferous saxifrage.