I wish there were ten of ME when it comes time to divide overgrown clumps of daylilies. What a job!!! One downfall of mine is, I wait too long.

Here is how I do it.

Hush Little Baby; purchased in 2011; noticed a decrease in blooms this year.
Size of the root ball about 18" x 12".



Next, gently knock out as much soil as possible with the dandelion weeder. Notice that the leaves are trimmed back but I left the scapes taller. That really helps to hoist the heavy root ball around until the fans are divided. At that point I will trim the scapes back to the height of the leaves.



Next it goes to the spraying station. On the "jet" setting wash out as much soil as possible. You can see by the break in the root ball I had planted the fans originally in two groups.



Next it goes into a tub of water to soak for at least a few hours. Then I try to ease the roots apart. In this case I needed to get aggressive with the dandelion tool again to cut into the root ball in several places to break the clump up into more workable chunks.



Next the roots get washed in bleach water (ratio of water to bleach is 9:1), then rinsed in plain water, then laid out to dry. After they dry off, I replant them. I ended up with 35 fans (not counting the ones that got broken and tossed out).



I think the "key" is recognizing WHEN it's time, and that will certainly differ from one daylily to another. One key sign is when you notice less blooms or scapes than the previous year. If you see that several years in a row, it's probably past time to divide. (Often turns out that's what I do.)
Let's hear from others how they do it.

I do almost exactly as you do. Actually though, I'm not sure I've ever had a decrease in blooms from needing to be divided, except for Stella d'oro. It is my motto to not mess with what is working so I have many large clumps, but sometimes it has to be done. They just start taking up too much space. Some daylilies are just so easy to divide, just washing them off with the hose & they practically fall apart, wish they all were so easy. Others entwine & have to be cut apart. Most fall somewhere in between.

@petruske when you replant the fans once they are dry, how many fans do you plant together? Will you pick 5-10 fans to put back in the original location?

I try to plant 5 fans in a clump. I often just put them back in the same spot, adding some compost to the soil first.

I've been planting 11 fans into the same spot they came from. I do spread them out a bit more though. I do mix compost and alfalfa pellets in the spot too.

The excess fans go to the back of my garden for now.