I use a very sharp filet knife and cut a deep (1-3", depending upon the size of the ball) X in the bottom of the rootball. Then I spread the 4 sections outward and when placing them in the ground, or larger pot, I make sure the 4 segments stay spread by forcing them down onto a mound of soil.

I also tease loose smaller roots all around the sides of the rootball.

I also water daily and with smaller plants twice daily.

Donn,

Thanks. I didn't do the mound, just spread the roots. Hopefully the Muhly plants are OK, one looks pretty good but the other really looks like its in shock, it was the more root bound one but it wasn't that root bound. These were rather pricey large plants so I'm a bit concerned here. I now wonder if they'd been in a protected greenhouse environment and it was too much sun too quick? Maybe I mistakenly assumed since they had them sitting outside at the store they were ready to just plant and it is Fall and not July.

Time will tell.