Sempervivum and Jovibarba

[TheOnionMan]

A sempervivum planter: color transitions

Hey semp fans, I've had a low bowl shaped plastic container planted with 3 semps for the past 4-5 years, and it sits on the lower step of my deck year round, where I get to view it continuously. The amazing thing about semps, is to watch their foliar color transformation, and rosette transformations through the months.

The 3 plants are:
Sempervivum ciliosum var. borisii - upper left, one of the best ever species.
Jovibarba heuffelii 'Torrid Zone' - upper right, a superb descriptively named Bill Nixon hybrid.
Sempervivum 'Nouveau Pastel' - a 1956 hybrid from Nicholas Moore, one of the most unique, a true semp chameleon.

For the winter, the semps "hunker down" and retreat into a compressed winter mode, showing lots of dried remains of past leaves acting as a "ruff" around each rosette.  In spring they grow out of the winter mode and start expanding, taking on vivid colors.  In Photo 1, the rosettes still show old dead leaves around each rosette.  Just a few days later, with abnormal heat and sun here in New England spring 2010, suddenly the rosettes awaken and start taking on some color and rosette expansion (photo 2).  Photo 3 shows strong coloring and rosette growth, the amazing chameleon S. 'Nouveau Pastel' is a luscious toffee color, and 'Torrid Zone' is... hot torrid red with inviting green centers.  Photo 3a is a side view showing that 'Nouveau Pastel' is one of those semps that forms tall one-sided "reaching" rosettes... 'Torrid Zone' also reaches upwards.  In photo 4 taken the end of July, we arrive at the color apex, with some flowering happening (thank goodness not much though)... 'Torrid Zone' is hotter red than ever after losing the cool green center, and 'Nouveau Pastel' is getting so crowded that it accentuates coffee brown centers.

Some semp species and hybrids put out "chicks" on long stolons, and this can be difficult to deal with.  These three semp/jovs were selected because of their dense clumping habit with chicks close to the parent.

[Armin]

Mark,
a nice potful and a interesting picture sequence showing the change in growth and color differences!

I have a few sempervivium hybrids, very hardy and modest growers, bought at the local garden centers.
But I can't give cv. names to them as it was not mentioned on the labels.

Maybe you like the link http://www.semper-vivum.de/sempervivum

[cohan]

nice planter and plants, mark--the toffee colour is really great!
 unfortunately, while they are hardy here, they are not hardy in small/shallow pots--as i learned the hard way the previous winter--losing several plants in a 14inch square deep pot!
i was lucky to get a number of nice species and cultivars from europe last year, all still small and in pots (sunk in the soil over winter, i think they are mostly ok, but just thawing, so its soon to tell)..
this year, hopefully i will be able to get them in the ground this year--maybe  a raised bed in front of the house, so i can watch them through the year as well...

[TheOnionMan]

Mark,
a nice potful and a interesting picture sequence showing the change in growth and color differences!
Maybe you like the link http://www.semper-vivum.de/sempervivum

Armin - darn!  I just lost two hours time looking at each and every Semp hybrid and species on the German Sempervivum site, instead of working outside   Judging from some of the gorgeous colors and forms, Germany is one of the semp hybridization hot spots.  Using Google translate, I'm not sure the translations are very good, so couldn't determine if they ship overseas (outside the EU).  Some of those orange and yellowish tones ones are delectable, as are the sombre dark ones.

Cohan - I have lost some in pots or above ground planters too, I think some are not as hardy as others, or more sensative to winter moisture.  And, I think semps benefit from a more consistent level of temperature and moisture which is easier to achieve in the ground rather than in a planter.  Do look at the link Armin provided (it is useful to use Google Translate feature if you don't read German), and feast you eyes on the 300+ cultivars and hybrids.

[cohan]

thanks mark--i have seen  that site, and you may also enjoy
http://www.carlodewilde.nl/

[Graham Catlow]

Hi Mark and other Sempervivum enthusiasts,
I'm pleased you started this thread and am surprised there hasn't been one before.

I have a small collection some in the garden and others in pots and the plantpot saucers that the S. 'Lion King' in the photo posted on the Edinburgh and Lothians Show thread is growing in.

I drill as many 10mm holes as I dare in the bottom and then cover these with a weed suppressant membrane to stop them blocking. Next is a layer of pea sized gravel and then the compost. JI No.2, grit sand and grit. I don't know the quantities I just know when it looks right. The single rosette was planted and the sandstone slabs were placed on the top. As the 'chickens' developed the stolons were directed to where I wanted them to go or they were nipped off and planted where I wanted them. This is nearly a year old now. I think the 'hen' is going to flower this year which will be a nuisance for something with such a large rosette that will then die. I hate it when they do that!!!

I will post some photos over the next few days and weeks as I get the time and they fully wake up.

To be going on with here is a photo of S. 'Hey Hey' in the garden that I have on file.

Graham

[Graham Catlow]

Sorry Mark,
I had trouble sending the last post and then didn't say how much I liked your trio. I especially like the Jovibarba. The colour is amazing.

Graham

[TheOnionMan]

Sorry Mark,
I had trouble sending the last post and then didn't say how much I liked your trio. I especially like the Jovibarba. The colour is amazing.

Graham

Hi Graham, glad that you and other semp fanciers are here to participate on this topic.  My understanding is, you are also responsible for the marvelous pan of S. ciliosum var. galicicum... spectacular, looks like a Rebutia or Mammillaria.  It's been requested in the "Edinburgh and the Lothians show 2010" thread that you keep us posted when your S. ciliosum galicicum flowers... judging from how many are starting to elongate in that pan, you're going to have a bumper crop of flowering, not that you want that, but even so, it'll be a mass of yellow flowers. Does it normally have lots of flowering rosettes?  Thanks for giving details how you grow your plants.

The Jovibarba heuffelii 'Torrid Zone' is one of Bill Nixon's hybrids, among the best and brightest of the heuffs.  Mr. Nixon lives about a 1-hour drive from here, also in Massachusetts, USA.  He was very active in the days of much Semp fancy (1960s-80s), with the likes of David Ford, Peter Mitchell, Ed Skrocki, and many others, and he published the Sempervivum Fanciers Association Newsletter.

Here's another of Bill Nixon's hybrids (or at least I think it his), Jovibarba heuffelii 'Gold Bug'.  It's rather slow growing, and never bulks up too well, and the yellow red-tipped color is short-lived in spring.  I still have it, almost fully encased in moss, must get it replanted tomorrow in a better scenario.  In my photo, ignore the terrible whitish gravel.

And hey, Hey Hey looks great growing in the rocks as you have it.

[Lesley Cox]

So what makes a Sempervivum a Sempervivum and a Jovibarba a Jovibarba? 

[cohan]

So what makes a Sempervivum a Sempervivum and a Jovibarba a Jovibarba? 

distinction is by floral characters, and species do not hybridise across the line, despite sharing habitat; those comments are very briefly taken from the  below link-
here's a discussion of the somewhat controversial subject--the species which should be separated are clear enough, but the larger validity of the separation is debatable:
http://stalikez.info/fsm/semp/site/jov_gb.php?clc=12&zc=AeHa1b1g1f1f1iAdMzu1g

[Graham Catlow]

Hi Mark,
Unfortunately the S. ciliosum var. galicicum isn't mine, but I wish it was. Gail posted it as being at the London show the previous week.

Graham

[Lesley Cox]

Thanks Cohan.

[TheOnionMan]

If I could only grow one Sempervivum, it would probably be S. ciliosum var. borisii.  It grows ultra tight and hummocky, and always fresh looking.  In late fall and winter, the low flat-topped rosettes are densely packed, and those ciliate tufts at the end of each leaf make little points of light on the rosettes.  The first photo is taken in mid October, and I think I like it best in its winter guise.  Depending on conditions, spring color can take on rich pink coloration.

The second photo shows the plant in mid June, where the rosettes open up and the silver frosting of cilia catches sunlight to make the rosettes glimmer.  So far as sempervivum blooms go, some are tall and awkward, weirdly interesting, or ugly depending on your take on such things. But with S. ciliosum, the flowers are held in more compact heads and are an appealing chartreuse yellow color.  Since the flowering rosette dies after flowering,  this species fortunately rarely flowers, so no worries about overly abundant flowering to ruin an otherwise fine semp clump.

[Lesley Cox]

An enormous flower head and stem for a plant with such little rosettes.

[cohan]

If I could only grow one Sempervivum, it would probably be S. ciliosum var. borisii.  It grows ultra tight and hummocky, and always fresh looking.  In late fall and winter, the low flat-topped rosettes are densely packed, and those ciliate tufts at the end of each leaf make little points of light on the rosettes.  The first photo is taken in mid October, and I think I like it best in its winter guise.  Depending on conditions, spring color can take on rich pink coloration.

The second photo shows the plant in mid June, where the rosettes open up and the silver frosting of cilia catches sunlight to make the rosettes glimmer.  So far as sempervivum blooms go, some are tall and awkward, weirdly interesting, or ugly depending on your take on such things. But with S. ciliosum, the flowers are held in more compact heads and are an appealing chartreuse yellow color.  Since the flowering rosette dies after flowering,  this species fortunately rarely flowers, so no worries about overly abundant flowering to ruin an otherwise fine semp clump.

this is a favourite of mine, as well--i have what i presume is this, bought unnamed locally a couple of years ago--it was the one semp that survived the 14" square pot i mentioned, (winter 08/09); when i got it (presumably grown in milder british columbia and sold here) it was quite open in form, and began to close up tightly in autumn--but, my climate being much harsher than yours--it has remained in that closed up state since, all through last summer, even though it grew considerably, the rosettes have stayed small and dense and tightly shut; it seems fine again after another winter, and spring which has seen days to at least 14C (likely higher where it is in front of the house) as well as lows recently to -10 to -15C; back up to +16 days in a couple.....