Cutting back will stop the flopping.

Dividing may work also. I've had these for a few years. THey don't flop when young, but after several years the clump gets quite large and then they flop. By dividing, they stay tall and strong again (for a few years.)

Full sun will keep them straighter than part shade.

I agree. I cut mine back and have much nicer plants when in bloom. You can also use a peony ring or stake the plants in some other way to keep them upright.

Jen

Dividing every few years will help. Older plants have too much organic matter in their center, and this rots. To keep these types of sedums upright:

1) Full sun
2) Lean, quick-draining soil; almost no organic matter at all (compost, composted leaves, etc. - your worst soil)
3) Next to no water
4) No nutrition (fertilizer, compost, etc.)

If they are grown in this way, cutting back isn't all that necessary, though occasional divisions are.

Great advice, thanks! I've got another sedum over in a very hot, dry, and barren area next to the driveway, and it thrives and never gets floppy. I think I'll be moving the sedum patch again, LOL.

If I do cut them back, when is the best time of year to do that? I heard June, but the frosty morns are pretty full and lanky by April for me in the PNW. They are the first to come up in Jan, and are already about a foot tall by April.

And do you just cut them down by half, or is pinching/cutting the flower heads off a better thing to do?

I don't have Frosty morn, but I have several other types of sedum that tend to get tall and flop after a few years. I don't divide them much, but I do cut them back by half when they reach about 8"-10". This has really helped in keeping them looking good and straight. I've used some of the ends I've cut to start new patches. I trim off the bottom leaves, turn some soil over and stick them in the soil. I do water those regularly for the 1st summer...just so the roots take well. After that they're fine. Btw, I wouldn't cut them back if they have their flower heads growing. Since you're in a milder zone, you'll be doing it before June. Do it whenever yours are about 8" or so. You may have a later bloom, but not much.
Good luck and enjoy!

Kat

Brunosonio,
Here is what Tracy DiSabato-Aust says in "The Well Tended Perennial Garden" about a different sedum, 'Autumn Joy', but I have followed this with my own 'Frosty Morn':

"Plants can be cut back to 4 in. when they are about 8 in. tall, normally in early June. They could also be pinched at this time. Many gardeners prefer the results obtained from pinching as compared to cutting back, claiming that cutting back causes the plant to callus and break off in winter weather, whereas pinching does not".

Good luck with which ever method you try! I've done it both ways and have to say that I really couldn't tell the difference.

PattiOh

Thanks, patti and kat...good to know. I'll try that trick this year...since they grow so quickly for me, it shouldn't be a disaster if they look bad at first. They usually hit the 8" mark about March or early April. If I don't cut them back, they will bet upwards of 2-3 feet tall at times! Then they curve down, flop over, and start growing up again.

They don't look bad in the beds, but they end up taking up a lot of room around them. Last year I propped them up with aggressive shrubby herbs such as Sicilian oregano (great color contrast to the white Frosty Morns), summer savory and marjoram.

I guess this mild PNW climate is too good for them, LOL.

After I cut mine back, I planted the cuttings and they caught up with the rest of the bunch - now I have TOO many Frosty Morns - (can you have too many??LOL) - Carrie

Carrie, you know it amazes me that some sedum cost a pretty penny to buy. They are so easy to multiply they shouldn't cost much at all. I have Black Jack that I'm planning on starting some new ones this Spring.
Brunosonio, my Black Jack and Purple Emperor tend to sprawl out too. They bend like your Frosty Moms, but cutting them back should keep them in line.

Kat

Frosty Morn is by far my worst flopping sedum. Sedum alboroseum 'Mediovariegatum', a tall yellow variegated sedum which I bought at the same time in Spring 04 and planted on the opposite end of the same hot southwest facing & dryish (for me) bed near the house, is much bushier and upright than Frosty Morn.

The only other Sedum that I have that is nearly as bad as FM is Vera Jamison, one of the older purplish varieties which always sprawls open. Because Vera is actually a quite short sedum, it has not been as troublesome as FM which is always intruding on its neighbors & getting chopped up by the lawnmower as it lays on the grass - at least in my garden.

Since I really love the variegation on Frosty Morn and built a combo around it, I have put up with the flopping, but have to admit that I have taken to chopping if off by at least a quarter with hedge clippers or pruners several times a season to make it work. Fortunately the chopped pieces grow nicely when stuck back into the ground which helps give a fuller effect to what has been a rather thin dislay for me. IME, Frosty Morn has not proved to be a very robust sedum, I suppose because of the variegation.

BTW, Autumn Joy has never flopped for me in any of its several locations in my yard (usually on hills in front of shrubs or big grasses that suck up all the moisture), even though I have read of others who have had problems with AJ, so I was actually quite shocked by the poor performance of Frosty Morn. Gardening sure keeps you on your toes!! LOL.

Brunosonio - I don't mean to discourage you - maybe you have better conditions for FM than I do. Best Wishes, Leslie

Thanks Leslie...I had the same experience with the other sedums as you. My AJ's do really well when I plant them out in the hot sun and in a dry, poor soil. I made the mistake of planting a row of them behind some Provence lavendar, then planting some David phlox behind the AJ. In theory, it worked...the lavendar kicked in first, then the AJ, then the phlox, then the AJ appeared again in Oct after I trim the phlox and lavendar down. But after 3 years the AJ just got overwhelmed by the others, and didn't get enough sun, so they've pretty much only sent up 3 shoots per plant this summer.

So I'm ripping them out, dividing them, and moving them somewhere else. I have a feeling that dividing my FM's, and cutting them down a bit, will rejuvinate them. They are also about 4 years old by now, and starting to show their age.

I found a new German variety with incrediblely dark red flowers and very dark green leaves (sorry, am not really good at memorizing the Latin names). So far, it's been a winner, staying relatively upright. It looks fantastic next to the FM and some low lying Vera Jamison. I planted them all around and under a Persian parrotia (ironwood) shrub/tree that pretty much soaks up all moisture. They seem to thrive there. This is all directly western facing so it gets blasted with full sun in the summer.

And I've got volunteers coming up all over the place!