Sempervivum and Jovibarba

[TheOnionMan]

Armin: thanks for the language help on the German semp web site.  If I find a job or win the lottery, I'll be ordering
Gail: thanks for identifying who showed that terrific pan of S. ciliosum var. galicicum

Finally found two photos of my semps, back in the year 2001, seen growing in pots woefully too small for long-term, but the intent was to create new garden beds for my 200 semps in the shorter term, but this never happened, most of the plants slowly suffered and dwindled away over the years.  The photos taken in July, show that many take on their brightest colors in midsummer.

[cohan]

more nice semps!
john--great collection! but, peat?? anything potted in peat needs to be constantly repotted since the awful stuff turns into mud bricks in no time,

Cohan  - Here peat mixed with anything organic or soil turns to black soup in time.  We are using coir in mixes for other things but still use some peat but those plants get in the ground rather soon.  Friends in Denmark grow many things in pure peat and as long as they use inorganic fertilizers the peat doesn't break down. They make sure their peat block walls are separated from the lawn or any soil or compost by a barrier of sand.  They grow incredible plants, I was stunned to see their Lewisia tweedyi in the peat walls!

johnw

i've never used peat outdoors, but of course virtually all commercial soil mixes in canada have peat in them, so i have had indoor plants in it--after a while it becomes almost impossible to water; several years ago, i switched all of my cacti and succulents to a loam based soil, and that involved soaking, prying, scraping and in the end removing nearly all of the roots before i could get rid of the awful stuff!(it was not mixed with anything organic in the nursery mixes); it does seem to attract mealybugs, and others mention its a big attractor to fungus gnats as well... so i avoid the stuff entirely (which means using almost no commercial soils, although i find one that i think is made with composted bark (still mixed with other things), and its only for woodland seeds-never for c+s..

i wonder what is different with the peat in denmark that it doesn't break down? just separation from anything organic?-but again, no organics in the commercial mixes i've bought indoor plants in, and certainly breaks down;
 i've never used it outdoors here, though at some point i will be planting some things that may like it outdoors, and i will probably harvest a bit of peaty organic soil from my own acreage for that...

[TheOnionMan]

I believe one day I shall take up hybridizing sempervivums, maybe a fun hobby when I retire.  Only once I tried my hand at hybridizing, here's a photo showing my cross between two species, S. zeleborii x pittonii. You can see some variation in the rosettes.  Since the seed is as small as dust particles, my seedling flat was perhaps 1000 seedlings or more, the problem is how to handle picking out and growing on so many tiny seedlings.  So, I took the lazy approach, and potted up 3 or 4 big clumps of seedlings, and only the strongest would survive in their fight for space and light.  Not a very scientific approach, but interesting to observe the results.

Why did I pick those two species, well... because they were growing next to each other in a planter and flowering at the same time

[johnw]

Cohan  - The Danes I know get very coarse peat and peat blocks from Sweden. It's beautiful stuff.  By the way they mulch their peat beds if they sag a bit with more peat, never bark - again because it will degrade the peat.

johnw

[TheOnionMan]

Cohan  - The Danes I know get very coarse peat and peat blocks from Sweden. It's beautiful stuff.  By the way they mulch their peat beds if they sag a bit with more peat, never bark - again because it will degrade the peat.

johnw

I have to go with Cohan on this one; one of my pet peeves are many large scale nursery growers, the ones that supply the large "box chain stores" as well as smaller commercial nurseries, is the overuse of peat-based mixes.  When tipping out such plants, the root ball an inpenetrable hard lump, which will never sufficiently merge with surrounding soil, and when planting such grown plants, they invariably die.  I have tried blasting off all the peat with a water stream, then plant, but only slightly imprived results, 3 out of 4 will die.

I started taking a cue from the way Darrell Probst and Karen Perkins of Garden Vision Epimediums grow their plants, using a large percentage of shredded bark mulch (usually pine of cedar, or both mixed) in addition to soil.  The aeration is great, and plants are ready to grow on with great rapidity.  When I pot up many items now, such as woodland plants, I use at least 50% partially decomposed pine bark mulch.  As an aside, I'm imprssed with how seed will germinate directly in decomposed pine bark mulch, seems to have the right moisture retention yet with aeration.

[johnw]

Mark - No peat is probably a wise decision for your hot summer climate. Many rhodos here and imported are grown in peat and bark and refuse to send roots out.  We always cut big pie-shaped wedges out of the rootball before planting.  Others plant as is and blast the rootball with a very strong jet of water after planting.  We use alot of well-rotted bark in our mixes but have found soil in the mix - with ericaceous plants - leads to root rot in a wet summer.

Grower friends in Ontario have eliminated peat in their rhodo mix and now go with bark & perlite.  Their plants now have much stronger root systems and they've had a dramatic decrease in phytophthora.

BTW way our local peat is fine stuff, the worst grade; the best is sent to Japan.  I really like coir  - chunky and regular - but it's not cheap and does degrade in time in this wet climate.

Attached Danish rhodo garden - all plants in pure coarse peat. Sorry this is hardly on the Semp topic.

johnw

[cohan]

Cohan  - The Danes I know get very coarse peat and peat blocks from Sweden. It's beautiful stuff.  By the way they mulch their peat beds if they sag a bit with more peat, never bark - again because it will degrade the peat.

johnw

very interesting, john, something to keep in mind, for sure..

[Graham Catlow]

This one is Sempervivum 'Walcotts Variety'
The main plant filled the whole area with the offsets touching the the outer edges in the summer. It receded during the winter. This is its winter colour which changes to a blue/grey colour in the summer.

'Hen and chicks' is this an American term as I have never heard of it over here until recently. The common name in the UK is Houseleek.

Maggis Perth Show thread has some Semps from the show. Another borisii.

Graham

[Maggi Young]

[quote ]
Maggi' posts  in the Perth Show thread hve some Semps from the show.


[/quote]
Yes, see here : http://www.srgc.org.uk/smf/index.php?topic=5350.0

 and in the Edinburgh Show pages there are some more pix too:
http://www.srgc.org.uk/smf/index.php?topic=5303.msg148964#msg148964

[TheOnionMan]

This one is Sempervivum 'Walcotts Variety'
The main plant filled the whole area with the offsets touching the the outer edges in the summer. It receded during the winter. This is its winter colour which changes to a blue/grey colour in the summer.

'Hen and chicks' is this an American term as I have never heard of it over here until recently. The common name in the UK is Houseleek.

Maggis Perth Show thread has some Semps from the show. Another borisii.

Graham

Wolcott's Variety is an old cultivar, one that can be commonly found in nursery centers here in the USA.  It is interesting seeing yours in winter color, as it illustrates how the winter-red coloration of many semps can be misleading... because it is the summer color for which certain cultivars are best known, and Wolcott's Variety is a lovely blue-grey as you say (with hints of pink) in summer.

While I'm not usually a fan of common names, I do like the name Hens and Chicks, as it is so whimsically descriptive of their growth cycle.

Question:  I see in Maggi's links to the plant shows, that Jovibarba species are listed as Sempervivum (I spied J. sobolifera shown as Sempervivum sobolifera).  What's the standing of Jovibarba as a valid genus?

[johnw]

Yet another Semp trough in need of an overhaul.

johnw

[TheOnionMan]

Yet another Semp trough in need of an obverhaul.

johnw

Well, it still looks fine to me... although a bit of demossing might be in order.... I also have the problem of semp planters getting mossy.  What varieties are in that trough, is that J. allionii or J. sobolifera along the top?

[johnw]

Yet another Semp trough in need of an obverhaul.

johnw

Well, it still looks fine to me... although a bit of demossing might be in order.... I also have the problem of semp planters getting mossy.  What varieties are in that trough, is that J. allionii or J. sobolifera along the top?

Mark - This is where I could get into big trouble.  The trough is so old the plants may have moved but accoring to the labels:

the upper red prolific one says Sempervivum ex Lohbrunner that Ethel Lohbrunner gave us.

the middle smokey red one S. Ritton

and the one just below those two and larger, Sempervivum reginae-amaliae.

I have to do a cross check of those in pots as there are two other labels with no plants. The third label is of a goner - a spectacular bright yellow from Rex Murfitt that never offset and finally flowered.

johnw

[cohan]

Yet another Semp trough in need of an obverhaul.

johnw

looks great overall--if anything just a little empty in the front..
i'm still not sure i understand the problem with moss--it doesnt seem to have hurt the plants, and i think it looks great around the plants, so what is the issue?? when i planted my big pot with semps and sedum, i planted bits of moss on purpose, though they haven't really taken off yet...lol

[johnw]

Yet another Semp trough in need of an obverhaul.

johnw

looks great overall--if anything just a little empty in the front..
i'm still not sure i understand the problem with moss--it doesnt seem to have hurt the plants, and i think it looks great around the plants, so what is the issue?? when i planted my big pot with semps and sedum, i planted bits of moss on purpose, though they haven't really taken off yet...lol

Coahn - If moss isn't dealt with quickly in this climate it will swamp everything. Witness my neighbor's garage roof, northside.  He went on sabbatical and came back to this.

johnw