I always had good results from cutting back my floppy yarrows, although I usually did this well before they started blooming. If you're concerned about this year's show, you might want to think about installing one or more peony rings. The kind that open and close with a hook will bundle and hold up floppy yarrows without damaging the plants.

I cut part of mine back about 3 weeks ago. It is slightly farther behind in blooms. The ones I didnt cut are about 5" taller, and starting to open. The cut ones have bloom but havent opened yet. Mine was always real floppy. So far no flop on any of it. I wonder if I cut it back after blooming if it reblooms?
TAmmy

Tammy, I was wondering that too. Mine started blooming about a month ago and look just about finished. I was wondering if they will rebloom if I cut them back. Glad you posted kentstar!

I agree with Lori. Peony rings are great. If you can get a large one it should go over the tall plants and you won't have to cut them. I have them on many of the taller plants in the garden and they blend into the foliage and aren't really noticeable. They are one of my favorite garden helpers and come in several different sizes which makes them even better.

hey kent ...

you have three ...

cut one... and give it two weeks ... and then decide whether the other two will get a haircut or be left alone ... i have always found that i will remember the lesson of an experiment.. longer than i will remember a post.. conversation.. or something read in a book ...

before the cut.. trace down a main stem .. and look into the junction of a leaf and the trunk .. if you see a tiny bud .. on any type plant ... when you truncate the main.. that will trigger the dormant bud.. to become active ... and soon enough.. once active.. it will do what any flowering plant will do.. start flowering.. to procreate ...

finally.. in my experience.. floppy plants is an indication of over-fertilizing .. among other things ... food producing plants need a lot of food to make the result ..

however, a lot of flowers.. like this weed yarrow ... which grows all over my lawn [??? meadow???] most likely does not need the fert it is getting.. causing it to bolt [grow much too fast] and flop.. way too early in the season ...

but that is neither here nor there ...

experiment man!!!1

ken

ps: isnt yarrow what the indians used to make brown dye???? or was it yellow .... or did i dream it all ... lol

I'm sure I have it situated wrong anyway. It's around one of my hybrid tea roses, and that gets plenty of fertilizer. I did stake it but I'll probably end up moving it next season to somewhere leaner and drier. I don't know where as I'm out of room lol.
I did stake them with some circular grow through rings and did trim back after looking closely for any little nubs down farther on the stems. I guess this is my experiment. lol
I'll post results in a couple weeks...

In addition to cutting my yarrows back before bloom, I *always* cut them back after they bloomed, and generally got a second flush of flowers out of them.

BTW, They're yarrows, the "thyme" of the flowering perennial bed. Don't worry about abusing them. They can take it, pretty much, whatever "it" is. I suspect your could probably mow those puppies and they'd still come back and look good.

The circular grow-through rings are either tomato cages or peony rings (probably the latter :)).

There are enough achilleas in this particular colour which are not floppy. Check Chicago Botanical Garden page with evaluations of perennials. Why bother with floppy at all ??