Senior Member
Posts: 137
Joined: Mon Jul 03, 2006 7:47 am
Location: Greater Toronto Area-zone 4-5

monster sedum

Hey all,

My sedum are monsters. I have three of them. The are about 3 feet tall and three feet diameter. They are so heavy that they've started to separate in the middle. If I were to trim them back in June or July would they still bloom in September? but not be so tall and leggy?

Same with the cone flowers. This year one of them fell over it was so big and full of blossoms. I tied it to the fence but it just leaned over onto the rest of the plant. The bloom still came but the foliage didn't look so hot. If I were to trim it back in the spring or early summer would it become bushier and wider at the base?

Also...I lost my caryopteris this spring and I think it may have had something to do with the time of year it was pruned back. I've heard lots of them die regardless. I have the new one and about 6 babies from the one last year. Would you prune it fall, after the first hard frost or in spring?

Green Thumb
Posts: 439
Joined: Thu Nov 09, 2006 11:17 am
Location: Midcoast Maine, Zone 5b

I think your sedums need to be divided. IME they usually start to open up in the centers if they aren't divided every third year or so. Too much shade or fertilizer can also cause floppy growth. I have spoken with gardeners who have successfully pinched them back in early June but I haven't tried this strategy.

I have tried cutting back Echinacea in early June. It does reduce the ultimate height of the plants but it also delays bloom which may or may not be a desirable outcome. Again shade or overly rich soils leads to floppier plants.

Caryopteris are very sensitive to less than ideal drainage. Late winter/early spring precipitation and freeze thaw cycles can be fatal if water gets trapped around the roots. I have tried both just removing the dead wood and stooling them in early spring (the amount of deadwood usually dictates the choice), either option can be successful. I would not advise pruning them in the fall.

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