Outdoor Sempervivum Question

[Adastra1018]

I wasn't able to find a thread on this already, so I thought I'd ask. I'm in zone 5, (Southeast Michigan) and I'm planning on doing an outdoor garden with sempervivums along with some other zone 5 hardy cactus and succulents. Even though semps thrive in this climate, I wonder about the rain and if anyone has ever had problems with water collecting in the crowns and causing rot? Are there any precautions I should take when I'm ready to plant other than ensuring they're in the proper soil mix? Every summer has it's quirks. One year we had so much rain we barely had dry spells last more than several days if I remember correctly. Then sometimes we have drier summers. Last summer was much hotter than normal and very humid.

[ElieEstephane]

Sempervivums usually love rocky soil which has lots of grit and is free draining. That should be your priority. As far as rain and snow, they are quite tolerant. I've had one at my mountain house in zone 6b and it lived there happily for some 15-16 years where it rained it a lot in winterand spent the winter covered by several feet of snow. It also was watered lot in summer as it is surrounded by flowers.
I only lost it last spring. A combination of the stem getting too long with age, being covered with grass which prevented evaporation and being shaded by a growing apricot tree lead to stem rot. However, i rerooted the rosette and it lives happily with me now in a pot

[DesertSun]

I haven't grown them, but I read that they do not love the heat, so I think that they must thrive in your climate. In mine there is no way they could withstand our summers.

[ElieEstephane]

Oh i meant 9a in my previous post! Sorry for the error.
Yes they don't like the heat but it doesn't harm them. They will just go dormant. Provide them with shade during your hottest month and they will be okay!

[Adastra1018]

I plan to give them partial shade but they may end up in full sun depending on the other species I'm growing with them. I can set up shade cloth as suggested when necessary. Typically our summers are on the mild side. Still fairly hot but usually in the 80s. We get a hotter stretch in August, but anything other than that is atypical. I mostly worry about water in the crowns. Guess I'll just have to keep an eye on them when it rains.

Thanks!!

[Grimm]

They cope perfectly well with rainy, damp, Britain so I would be surprised if they're not fine where you are. I have tectorum (including a monstrous one), calcareum and arachnoideum all outside all through the year. Last year I put most of them in a gravel bed and they've got through winter just fine. It might be worth checking a few UK Semp sites/forums for advice if they're not too common where you are

[lemonFresh]

Hello! I am in zone 5a. My favorite thing to grow outside is semperviviums. I live near a wetland, so the weather alternates between dry and humid. I grow them on rocks, in cinderblocks, or in dirt.
If planted at an angle, my semperviviums don't hold much water in the crown (with the exception of arachnoideum).
During dry spells, I sometimes spray them with the hose. Even then, I have never lost a sempervivium to water on the rosette. (Just watch out for overwatering)
I have only killed them by putting them in direct sun (the outer leaves burn, and curl around to protect the inner ones), or by making them so happy that they bloom.

[Adastra1018]

Thanks for your input! Guess I don't have to worry much then. I've accidentally lost several succulents to crown rot, including some semps but it was a ton of rain, and I hadn't had a chance to replant them from the container they came in from the store. They were also in mostly shade so they never had a real chance to dry out. My other succs rotted because I just didn't notice the water as careful as I was. Thought it all dried but it didn't and they were indoors. Anyway, the thought of leaving them in the rain made me anxious but I've been reassured so it's just a matter of time before I do this!

[nachtkrabb]

Hi Adastra1018,
I live in the South of Germany: Winters with snow, Summers pretty hot, sometimes pretty wet, sometimes too dry. I grow Sempervivum outdoors on the balkony in flowerpots with standard soil all year round. I rarely water them, never protect them from rain nor shine, they thrive. This year they seem to have an appointment to flower -- they do it all. Also at my parent's place, 25km away. Wherever I go, I see them flowering. Not for the first time, but I haven't noted down the cycle yet, it's at least 3years.

DSCN9210-Sempervivum.JPG (179.83 KiB) Viewed 1686 times

What I want to say: We don't make a fuss about them here. "Sempervivum" means "Eternal Life": They don't need much. They are more or less weeds here, often growing on bare stone, but also a fixed component of traditional farmer's gardens at least in the South of Germany. During the Medieval ages, people threw them up onto their roofs all over Europe where the plants grew: People believed that the lightning wouldn't strike their house then. Well, as houses of simple people were simple huts with low roofs, the lightning could glide and jump from a wet and succulent planted roof into the ground easily. So it's true, they are a protection.


These days, they are often used in cities on flat roofs to form coloured patterns: decoration, cooling of the house during summer / heating during winter, helping to better the citie's air..... The planting is even aided financially by Stuttgart.
Somehow we are back at the MAs again.


Good luck & good fun with them!
N.