Here's a couple of links that might be some help...

http://www.marthastewart.com/dicentra-spectabilis

http://propagatingperennials.blogspot.com/2008/05/dicentra-spectabilis-bleeding-heart.html

I've found when I divide mine there is usually a natural split of the plant from the base (where it is growing out of the ground).

Thanks for these links. However, neither addresses my specific question about splitting the root ball and how to do it. I'll keep digging, but if anyone can help, please let me know.

It's not exactly brain surgery, :-) and I haven't heard of that plant having a fussy reputation, so just about any reasonable way that works for you would probably be fine. If the root ball is really large, you may want to cut it down the middle at a natural division before you dig it out of the ground. That way a thick rootball won't try to slip away from the blade. Helps to have a sharp shovel, too.

If you water a lot, you could certainly do it anytime. Even now, if you were willing to sacrifice the flowers. I've done that many times and never lost a patient yet.

Good luck with it! You sound like at least a semi-experienced gardener...trust your intuition. Lots of transferrable skills in gardening.

Thanks, leavesweave. While it's not brain surgery, these 2 plants are now each 6 ft across. It's going to be a chore given their size. Each is 2 ft bigger than last year! I didn't want to dig them up without having a direction and expectation as to what I'll be dealing with. Thanks.

I've split mine several times over the past few years and it's definitely not fussy. I don't take the rootball out and I don't even look for a natural division. I just stick the spade straight down in the middle of the plant to split off whatever size section I want. I've done this 3 or 4 times now and the plant doesn't even seem to notice. It just keeps on growing and growing.

It's been a long time since I dug up my Grandma's Bleeding Hearts, but if I remember right, they don't have a lot of fibrous roots. Rather what they are more like is a mass of crooked and forked carrots. The soil will probably fall away quite easily if you dig the whole plant, but don't let that stop you. Divisions, as dirtbert says, naturally break apart. But if you'd rather just take shovelled pieces from the undug plant, that works fine too.

Thank you all. I'm feeling pretty good about what to do with your suggestions.

When I split mine and now I have 2 plants which span almost 10 feet (I didn't realize how successful my technique might be) LOL I just took the spade and ran it into the side of the clump. Lifted out the split piece and planted it about 4 feet away. Well the mother plant never skipped a beat and the two now became one monster!! So instead of going to all the work to dig the whole thing up, Just take a piece out and you should be fine. I did mine in late August I believe last year after the "show was over". I filled the hole left with manure and dug manure (from the bag) into the new planting hole. Hope this helps.

I did the same as "maidofshade" - twice now - and also have a "monster" growing. The first time I thought I killed it b/c after the split both parts died back (the cutting and the mother plant). The next year the mother plant was full of gusto, and the cuttings were great as well. In fact, for whatever reason, I now have baby plants popping up about two feet or so from the mother plant. I have no idea how they got there - cute little things that may end up at a plant swap someday