Once upon a time I started a semp garden. I constructed rock-lined, raised beds filled with the local native Canby soil excavated from a corner of my yard. I acquired every semp I could get my hands on and planted them throughout my rockery expecting them to take hold and grow and look beautiful.
The results? Spectacular beyond my expectations. Every last one of them was the picture of health and could grace the pages of a Sempervivum journal. In fact a couple did end up in Kevin's recent semp book. (pages 15, 28, 69, 171 thanx Kevin!) As my semps prospered I believed that either I had the midas touch or that semps were totally trivial to grow. Here's a reasonably typical example:


This continued for a few years but eventually my semps fell upon hard times. Here is 'Pepito' today. (the center portion of the pic)

This is below the average but at least it's still alive. I have a handful of name tags of cultivars that either bit the dust or I gave up on. I didn't give up on 'Pepito' because it is such a rare beauty.

So the question is... what the heck is going on?

Instead of blaming myself I used the weather as an excuse. The cold, wet winters do not make semps happy I was told and I do suppose that is true. So I blamed that. But that doesn't hold water cuz the first three years everything increased and prospered. And then there was the 'Purple Dazzler' affair. This semp started out awesome and slowly degraded like so many others. Many attempts were made to help this guy along in situ but its vigor continued downward. In desperation to save its life I moved it into a pot that I could move around and protect it from the nasty, wet winters. It immediately took off with furious growth. But far from protecting it, I neglected it and left it out for two straight winters. Did those nasty winters damage it? Not one little bit. So I have stopped blaming the weather.

'Purple Dazzler' did however offer a strong suggestion that soil was the real issue. The pot I had put it in was filled with a mixture of local soil, peat moss and compost. But then why had I had several years of great success in my semp garden with my local silty loam?

I think the common factor is air availability to the roots. The pot blend I used is light and fluffy and offers air penetration. And my semp garden soil was excavated and broken up, and so contained an abundance of air pockets of all sizes. But as time goes by this silty loam settles down and is very dense. The local vegetable farmers love it but they also do cover crops and regular discing, and they also use raised rows. I guess I could learn a thing or two from them.

Looking back at many new semp introductions into my declining semp garden, I have to confess to a cardinal sin. When planting offsets I would only open the soil just enough to insert the roots and expected that to work fine. And it sorta did and sorta didn't. I should have taken the opportunity to dig up as much soil as possible to make it easier for root expansion.

So... it is time for atonement. The root zone must be improved. Here is 'Pepito's new situation.

I cleared the gravel away and dug down 8 inches and worked the soil before replanting. Only time will tell if 'Pepito' will return to glory. A dose of QuickStart couldn't hurt.

Another problem area was a NOID calcareum which I dearly loved. It prospered well and then declined like so many others. I tried several times to rejuvenate it with offsets taken from a separate planting and those all failed. I was again being lazy and not working the soil. So here again I've finally made the effort to work the soil down 8 inches to lighten it up. Here's the new planting and we'll see if this one takes off.


The real solution it seems would be to re-dig the entire semp garden. I really, really don't want to do that. I'm wondering if there's an easier way. I picked out a few cultivars that were looking a bit weak and tried an experiment on them. I took a small trowel and drove it into the soil all around each semp and "popped" the soil up. Kind of like using a broadfork but on a much smaller scale. It will likely do some root damage but will also introduce some air into the soil. I'm trying this on 'Starshine', 'Silverine' and 'Purple Dazzler'. I have pictures of the first two so I can compare later.


I'm thinking if this works I can make it a yearly task to 'pop' the soil on the same day that I apply Quickstart in Spring. My guess is that it will improve the situation but never back to the glory days. I can live with that.

I'll try to remember to post updates here as I get results. It shouldn't be too long as I did all this at least two weeks ago.

Looking forward to your updates Tim!
Aeration, as you are probably aware is a big part of landscapers efforts to rejuvenate lawns, your efforts to open up the soil remind me of those fertilizer machines which plug little holes in the ground as they spread the nutrients.
The bonsai folks insist on using only large particle ingredients in their soils to keep the pores open and allow air transfer during watering. I read in a bonsai book that the air/soil around the roots becomes toxic as the roots digest nutrients, a porous soil allows for the area around the roots to be cleansed during watering, this could be important for semps to as they are also a slow growing plants (compared to things like vegetables and weeds). I've certainly found that they prefer open soil, the dense mud we have around here is no good for growing them, I tried growing my first "fancy" NoIDs in the native soil for three years before I picked up a book on hardy succulents to try and figure out why they weren't growing, when I dug them up to atone for my sin of using dense clay, the roots were in shockingly poor shape, stunted, gnarled and some were even being preyed upon by subterranean pests taking advantage of their weakened state. Never again will I subject sempervivum to such a tortured existence. Good fluffy soil is key. Very much hoping you're experiment pans out.
-Sol

So , Tim with a little time spent solving soil aeration problems, back to the real time killer, pickleball?

I've had this same problem with the sheep troughs I planted. Last summer I pulled the semps out, reworked the soil, adding pea gravel and pumice. Then replanted. They are thriving. My trouble was too much sand. I know better now.

Tim,

I think your analysis is correct. I have the best luck in my fairly fluffy premium perennial mix that seems never to really compact but even there the semps benefit from replanting to new soil every now and then.

I'm sure your garden will return to its former glory!

Kevin

Tim, I've seen the same thing at my place. I had a bed that was doing very well at 3 years old. Last summer it was glorious, and I was so happy with it. Now it looks terrible. We did have an extremely hard and cold winter, but they should have been ok. I will have to tear the whole thing up and re-do it.

Great observations Tim. Love the photo documentation.
I had to do the same thing with my raised beds every couple of years. I usually did it later in the growing season when I would downsize colonies. I would take the entire colony up and rework the area for each colony. I would usually replant mostly young offset to keep the colonies strong.
I look back and realize that is what happened to my 'Purple Dazzler'. It grew so well for me the first 2 or 3 years, then started into decline. Thanks to your gift of a new start, it is doing beautiful in the new raised bed with it's fluffy new soil. Thank you Tim.
Something I will do different from now on is to do this work in the early spring, instead of late summer/early fall. In the spring they are at the peak of regenerating. Perfect time to redo soil.
I agree with Kevin, your garden will be the show place we have all come to love.

Karen, don't let it overwhelm you. Just do a tiny piece at a time. Sometimes that is the only way we can get it done. How do you eat/repair an elephant/semp colony, one bite/colony at a time.

Thanks, Lynn. It is overwhelming at the moment. I will have to do it in small bites.

Great observations Tim. For quite some time now every year I've been selecting a bunch of clumps and redoing the soil under them, thin out the clumps, and replant the healthiest ones. In the long run it seems to be working well!

I can't believe I didnt recieve notifications for this thread! I am going ot have to catch up

I use around 50-60% sand added to old garden soil (primarily used to be pure garden soil from like home depot, I had tomatoes and veggies that used up all the nutrients from the preiovs year). Soil over time compacts and gets less aerated so i hope that adding more sand, gravel, and mulch bits will help.

My semp/sedum bed (and old semp bed) consisted of around a foot to six inches of sandy mix and there was a thin layer of bark/leaves, and than below that was pretty much just regular garden soil with 10-20% sand. This way the semps get water when I am away from the garden during droughts, whereas they dont get total wet feet. I do end up changing the mix to 100% sandy mix after the plants get fully established. Most don't care though.

If anyone has ever had containers before for a long time such as a year or two without soil maitenence you may see that the soil level "drops", because the soil compacts. Adding chunky things like bark bits, gravel, and sand help it stay fluffy.

You should be able to recycle old dirt by adding fluffy helper ingredients, if your budget can only afford sand/gravel. You'd probably want to add a bit o' fertilizer too.

I have found this can apply to plants grow in containers which is all I do.

The first couple of years they go great but then they start to decline and I find myself redoing them.

Typically I just start a whole new container with fresh soil, tear up the old colony, replant a whole bunch of them in the new soil and replant some in small pots to sell.

Interesting....

This may be off topic but I'll give it a shot. The other day I was peeing in one of my large compost bins and I fell in. I begin thrashing around in a vain attempt to get out. The more I struggled the deeper I got. I must have turned the pile 5 times with all the commotion. And it was extremely hot as I added copious amounts of greens two days prior. I actually started to decompose. My calls for help went unnoticed (or maybe they were noticed but no one cared) until a good Samaritan pulled me out. He offered me a beer but I declined as that how I got in the predicament in the first place. Anyway, my question is, have any of you used compost in your semp beds that actually contains part of your own body as part of the composted materials ?

Compost might be way to rich for semps John, with or without the human body parts.

Compost is way too rich for Semps. in anything but a very small amount as a top dressing.
Tim this is a great thread.
The pot of Purple Dazzler went on a huge journey towards decline this past winter. It was not sitting in full rain so was not getting too wet. I decided to re pot it. When I got all the plants out the soil seemed to have shrunk and when I dumped it out it was like a concrete rock. The plants had almost no roots. But not to worry.....they are replanted in 3 5/8 pots and some in bigger pots and all are now doing well. I wonder if this plant is an especially heavy feeder for a Semp???
All soil in beds and especially containers needs to be replenished at least every 2 years and the native soil where you live Tim is very rich and heavy. Excellent for the Dahlias and nursery crops which grow so well there, but not good for Semps and other alpines. I use a mix of composted bark, coir and pumice. This is a free draining mix that the Semps. and sedums really love. It's close to what they have in their native habitats, (bits of rock, twigs & leaves that get stuck in crevices in the rocks of the Alps etc) Sand is for desert plants not alpines and if you were to add sand to your existing soil I am pretty sure you would have concrete since your natural soil contains some clay.
It would be a huge job to redo your entire riverbed all at once but taking it a bit at a time is do able. Even one plant at a time will get it done eventually and will result in less mess in your yard. Best of luck with your new project.

Compost? Meh... i only have a small one that produces only enough for the veggies. (It is not big because other wise Max would roll around it )

Throwing dead leaves as a layer of dirt? Yea.

I have a layer to dead leaves around 6 inches under a sandy layer of dirt that keeps the soil moist and acts as long term fertilizer.

Jo Ann,
I agree. Sand alone is not good as a soil ammendment for semps. If you put only sand the soil becomes sort of like the texture of Gelato or fresh icecream. It is not airy. Adding gravel, pumice, or chunky mulch stuff (without dye) or perlite (not prefereed but it could work i guess) would fix that.

Thanks John

webesemps said:So , Tim with a little time spent solving soil aeration problems, back to the real time killer, pickleball?

Three hours a day and 5-7 days a week on the pickleball court does reduce time available for garden maintenance. Worse yet is the physical exhaustion. Last year I did let my semp garden get overrun with spurge, lambs ears, daisy and foxglove seeds by the millions. Under control now.

OK...time for a first glance. This is after 3 weeks I'm estimating.

Let's take a look at my rework of my NOID calcareum.
This one's a no-brainer. These offsets were transferred from a separate colony and are clearly establishing and growing and looking healthy. Previous attempts without rework failed miserably. I pretty much expected this result.


The second rework is of 'Pepito'. Not as obvious but the offsets were in pretty bad shape when I did this, and one of them even croaked. I'd say it's coming along slowly and I'm hopeful for a recovery. I can see improvement but more is needed.


Here is 'Starshine' that received a soil "lifting" by just pushing my trowel down in various places and popping the soil up, allowing air pockets. This is before and after. I'm gonna say there's some good improvement. Three weeks of spring weather and a dose of Quickstart might have helped, so I can't be too sure, but I am hopeful. I'll have to wait and see if a full recovery follows.




'Silverine' was another stubborn performer. It also received a soil lift and seems to have benefited nicely. It could be for the other reasons I mentioned but at least I can say that it's headed in the right direction and I'm not destroying its root system too badly.



Here is 'Silver Song' and 'Purple Dazzler' which both received a soil lift. I forgot to take the "before" pictures but here's what they look like today. 'Silver Song' has been a slow performer but now has (I believe) added a bit of growth and definitely looks better than last year.
I can't tell if 'Purple Dazzler' has grown any bit it seems healthy and is throwing a solid set offsets.
Seems like these two are at least headed in the right direction.



Very soon I will be fertilizing the whole semp garden. I will give each and every semp a soil lifting. I'll take large group pictures for general comparison. Then wait and see.

This has me considering cultivars that I have given up in the past. I figured they were just wimpy so why bother with them. Maybe my wimpy maintenance efforts were the real problem. I recall the fabulous 'Lavender and Old Lace' which grew wonderfully but tanked badly in later years. Similarly 'Pacific Blue Ice'. I think I'll give them both another try but with a little more TLC.

Atonement has begun... resurrection to follow.