Yup.

I grow them in the shade for just the foliage, in the sun for flowers.

Renee

Take it from someone with years of iris misery experience, or at least miseries until I learned that sun really makes all the difference in the world. Most of mine were in most shade so did bloom somewhat, but when I made a new bed in most sun, BOOM!!!!!! blooms galore. I wasn't even expecting all those blooms because I heard they don't bloom the spring after transplanting. They were so glorious that I'm expanding the bed and ordered lots of new ones. I'm on my way to becoming a irisaholic, lol.

So of course, give your grandmothers iris a try, what do you have to lose other than the little time it takes to plant it? Might not get blooms next spring, but wait until the following spring.

Maybe Grandma had them planted too deep and too close together all these years and that is why they didn't bloom for her. Never heard of planted them in shade either. Always thought they needed full sun. When you dig it up, hose all the dirt off and put into bleach solution, and check for Iris borers. Sorry I can't tell you the formula for the bleach solution. Maybe others here can tell you. Like Chocolateis2b8(a clever username!)told you, you might not get blooms the first spring; more than likely the following spring. Good Luck! Keep us posted, but put those babies in sun.

Anything I have planted in the shade either doesn't bloom or blooms poorly. I don't have anything in full shade, so most things bloom eventually. I have Edith Wolford growing in nearly every corner of the yard at the moment - the ones in the sun bloom like crazy and in the shadier locations, I might get one or two.

1 part bleach to 9 parts water. LaurieF covers the basics extremely well in her FAQ on bearded iris.