06/03/2025
This is a post that I was asked to make for another group. I thought it would be a good idea to share it here as well. Hope it helps.
I was asked to make a post about Sempervivum, commonly known as hen & chicks. Sempervivum are alpine plants. They thrive at the tops of mountains, in the grittiest mix, in the brightest sun. Most are hardy to zone US z3(-30°f). The ideal climate for them is in z4-z8. They can be overwintered indoors under lights but, most varieties will not thrive indoors long term. They do best outside, in our cold climate, through negative temperatures, and feet of snow. No protection needed. However, they do need to be acclimated before the real cold sets in. Just be sure they have a well draining substrate in the ground/pot.
If you are growing in containers, you go a zone up. So, if you are in z5, you can grow anything hardy to z6 in a container. Be sure the containers are very well draining. Hypertufa works very well for our cold climates because they are porous and survive our crazy weather, the snow, and the freeze/thaw cycles.
With thousands of hybrids it’s almost impossible to name a NOID. If you don’t know the name of your plant, you’re not likely to find out. Also, the seed produced from a bloom will produce nondescript hybrids (NOIDs). Saying that, it can be quite interesting to see what pops up in the garden over the years. And they do take years from seed. 😉
My hardy beds (MA/z5) are raised and amended with cactus soil and pumice, topped with river rock. I grow a lot of hardy plants and this is just the best I can give them here. You certainly don’t have to go to those extremes. However, even more so than other succulents, semps want their roots to dry out quickly. Considering they are covered in feet of snow a good part of the winter here, a good draining substrate is important.
Semps are best propagated from offshoots. Some sempervivum have a clumping habit, some will simply spread underground and pop up nearby. Some will surround the mother, some will grow off a stolon, some between the leaves, and some will multiply heads. They show up all over the gardens, especially the rollers. I mostly let them do their thing unless they are showing signs that they are struggling.
Semeprvivum are monocarpic plants. A plant will flower and go to seed just once in its lifetime. This is often caused by age, or stress factors. That plant will die back after bloom often producing many offsets (chicks).
Mother Nature is an amazing artist and these are some of her most sturdy beauties. You know how those of us in cold climates have zone envy for the folks that can keep plants outside all year? Well, these are the ones made for us. They are very low maintenance if given the right environment, and they will give you a different show in every season. Even through winter…as the snow melts off of them.
Here are some photos of my Massachusetts/zone 5 hardy beds through the years/seasons to reference some of the things I’ve mentioned above. Some photos are from mid winter, after a large snow melt. Hope this helps.