Hello friends,

I haven't posted in years, but I recently got a backyard, need advice, and this board used to be very supportive :)

I am planning to put a bunch of succulents behind a sitting wall. I have only had kalanchoes and always only in pots. What is the best way to water them? How many times? Are some of the these sensitive to the sun?
https://photos.app.goo.gl/Fk7P...

The area where I want to plant them is behind this sitting wall and it gets sun most of the day:
https://photos.app.goo.gl/wPgA...

One of the concerns I have is wether it will be fine to have the decorative rocks covering the area up to the stems. Will they get too hot? Will it make it not drain well or for me not to see if the plant needs water?

Another thing I am considering is using this cactus (that a neighbor gave me a couple of months ago) near a fence for a side of the house that is not very visible. I know these plants like to invade, so I cannot put them in many more places:
https://photos.app.goo.gl/zVhL...
(if you know what variety it is, that is a plus).
Thanks a lot!

María

I would advise caution about installing plants that small in the ground, especially if you are new to succulents (beyond potted Kalanchoes). Not to say you shouldn't try, but some of them might not make it through the summer. Our dry summers can be pretty brutal (combined with overhead sun) for young succulents, before they have a reasonable amount of succulence above ground (water reservoir) and root mass underground (for effective rehydration from sporadic watering).

My usual minimum size for putting in the ground is 3 gallon pot size (10 inches, full with roots) and I have made exceptions for a few plants in 8 inch pots that did well. Obviously anything's possible, this is just my ten years of experience putting succulents in the ground and watching to see who lived and died. To the extent I am extra careful to give regular care to the baby plants on the patio, I am kind of a slacker in the garden, which gets water every 2 weeks when there is no rain. Our climate is quite similar to yours except we get 10" of annual rainfall.

My suggestion would be to keep your plants in pots for a while, give them a comfortable, bright location and water attentively (when the soil is dry or almost dry, not sooner) so that they can bulk up, and then make your move in the fall, earliest. I try to only put plants in the ground in fall or winter, when we get most of our rain. Late spring and summer installations tend not to do as well. Again, not that you shouldn't try, just temper your expectations. If you want to install landscape plants now, go the nursery and find something bigger, in the size range I mentioned.

Top dressing landscape plants with gravel or small rocks is a fine idea, and that's what I do. You don't want to overdo it, a layer 1-2 rocks thick is perfect. Be aware that will slow down evaporation (which in the end is a good thing, within limits, once you're aware of it).

The green aloe in the last picture could be Aloe x nobilis, or something closely related, and it would be an excellent low-maintenance choice for your climate, with nice annual flowers, and it will clump but not out of hand.

As to your question about watering, those plants should do well in their current pots with weekly watering, approximately, provided you are able to provide strong light. At this point 50% shade is ideal, or part sun (2-6 hours of direct sun daily) but not full sun (>6h direct sun) until the fall.

Thank you very much for your post, it was very useful.

I will keep in mind all you say, although I am already disappointed to hear that I shouldn't replant my succulents until the fall. But I hear you that all you are saying is that I should not have very high expectations. So I may try putting in the ground only the bigger ones. I was afraid the fall would not be the best time to transplant because of the rains. What happens if it rains a lot? Is that not a problem?

I have spent a couple of hours this week emptying the rocks behind the sitting wall because my first realization is that there were too many, like 2 inches thick. So I will fill it up more with soil and, since the soil is kind of muddy there, I will make sure to add well draining soil and that way I'll kill two birds with one stone (on top of it all, I'll put only a fraction of the decorative rocks). Do you have a recommended mixture for the ground? Or should I just buy whatever says "for succulents"? Is there a difference in the soil to use depending on whether it is for pots or to plant in the ground?
(I just saw, after posting this response, that you created a thread on soil for people to share this, so I'm starting to read it. I'll need to continue tomorrow, as it is too late!)

For the smaller succulents that I should not move to the ground: is it a problem to plant several succulents together in a large pot?

Again, thank you so much! I've been digesting all you told during the week and observing my new babies to make sure I had all that I collected all that I wanted to ask before finishing my response

lameri said:I was afraid the fall would not be the best time to transplant because of the rains. What happens if it rains a lot? Is that not a problem?

Unless you're in some kind of heavy clay, I doubt you would need to worry about too much rain. You will need to plant your succulents with some fast draining soil around them (and I will get into amendments for the landscape). Whatever excess water that comes in the fall (or whenever) should ebb right away and that's the key for maintaining most succulents. There are all kinds of adaptations to allow succulents to tolerate some rainfall... in extreme cases people put them on little mounds of mostly rock so they never ever get wet feet. You won't need to do this, but you should pay attention to where the water goes when it rains.

You being in zone 10a (and that means proximity to the Pacific, very mild winters, low temps in summer) means that neither cold nor heat is really a factor. For any plant that might be stretched to its limit with respect to temperature tolerance (say 9b or 10a plants in your climate) the real sensitivity is associated with wet roots. Meaning that the only rainfall that will seriously stress your succulents, given your climate and proper installation, is persistent rainfall that comes when it is cold at night and does not warm up much during the day.

lameri said:Do you have a recommended mixture for the ground? Or should I just buy whatever says "for succulents"? Is there a difference in the soil to use depending on whether it is for pots or to plant in the ground?

Our native soil here is very sandy and rocky, in some places much more rock (>1/2") than actual soil (<1/2"), and I always plant on a slope (water goes downhill and away from the succulents). Your own modifications will vary based on the differences in soil and topography. If your existing soil is mostly clay (very fine particles) then you will need to do more to improve drainage, but if it is rocky like ours then introducing some compost would be a bigger priority. My advice would be to modify the existing soil by mixing it with an equal volume of compost and fine gravel (at the proportions you find most helpful). Doing this rather than adding new soil on top (only) means that your plants will tend to root out of the area of modification more easily, and be less constrained by the boundary between modified soil and native soil. It's more work but it's worth it, long term. I do this piecemeal so it's never a giant undertaking.

Any kind of soil "for succulents" will be helpful for amending soil in the landscape, if that's what's easily available to you. I typically mix in the bagged soil from my local nursery (what they give you when you ask for soil, there's only 1 option) which is mostly compost, plus maybe a quarter that volume of pumice for good luck (since there's already lots of rock in the soil).

Yes, soil for succulents in the ground will be different from soil for succulents in containers. Plants in containers require more strict attention to drainage, plants in the ground tend not to suffer as much from these issues except where climate presents special challenges. Obviously if you're mixing in native soil when you amend it, you've got something different there from what you'd put in pots right away, and I definitely do not recommend mixing in native soil for container culture, unless it's in small amounts and it's the right kind.

If any of this is not clear, just let me know.

Dear Baja_Costero,

Thanks again for your very detailed post!

I think my biggest challenge is that I don't know exactly how much grit I need to add--is 50% soil and 50% grit a good proportion? Our soil seems pretty muddy. It comes in part from a super good soil that was brought to us by some landscapers who helped us build a structure for a passion fruit tree a year ago. So obviously, they didn't think we needed well draining soil :)

From your post I have learned that I need a thicker layer of "good soil" (and not just a bit added on top), although I see that the aeoniums that I've had for a year have very short roots (despite their disproportionately tall stems). Is that not the case with the other "creatures" you see on my picture? How about a 10''-layer of good soil? I could mix the grit in those 10'' (below that would be the thin non-modified soil).

Regarding grit, it seems I can use perlite or pumice but the latter is better for the environment although more expensive, correct?

50/50 soil/grit should be good for the amendment (to be mixed 50/50 with native soil). A lot of succulents have pretty shallow roots (and do well in smallish pots) like your Aeoniums, but given a chance to expand in the ground they can root deeper. Sure, 10" is good. Maybe 12" is better.

Regarding pumice vs. perlite: the main difference is perlite is really light and will blow around, and probably be a bit messier because of that. I don't know if either is particularly good for the environment. Pumice comes out of a mine. You can also use lava rock, or various other kinds of fine gravel, depending on what's available to you. Avoid limestone, avoid shells, but pretty much anything else goes. Even construction sand can work for this purpose if you screen it first to remove the fines.

Great, I'll do 50/50 and will show for 10'' upwards. Should I add any fertilizer to the 50 native and 50 grit mixture?

As for inorganic matter, thank you, very informative. Two points:
1. I heard that construction sand would have too much lime?
2. I hear about perlite, but since I'll have the weed block and the decorative rock, won't that solve the problem of being blown out?

Thank you!

Adding fertilizer would be redundant if you're introducing organic matter when you amend the soil in the ground. Fertilizer is overrated for landscape succulents in my experience, and totally unnecessary for most succulent gardens provided there's a reasonable (not excessive) amount of organic matter in the ground. As much as I like to use low dose fertilizer for my container plants, I avoid it completely for the plants I put in the ground. I suppose if you've got nutrient poor soil and you are only amending with rock, then you might benefit from Osmocote or some slow release granules in there, but try going without first, before you start with the fertilizer. Fertilizer should never (ever) be necessary if you install plants with the right kind of amended soil. A year or two down the road maybe, but definitely not up front.

There are various forms of construction sand with other stuff in them, like wax or whatever (not good), and there's mortar which has cement in it (including lime) (not good), but just plain sand all by itself (no other ingredients) is pretty ideal for soil mixes, provided you screen out the fines to arrive at more of a fine grit than actual sand in the beach sense.

The weed block is some kind of fabric? I'm not sure I understand the setup, but make sure whatever you use alows the free passage of water/humidity and doesn't act to trap it in the soil, beyond the expected bare minimum.

To be honest I avoid perlite like the plague (mainly because of the dust that comes in the bag with it) so my experience is really limited. I can't really comment on mitigating its tendency to drift about, but having decorative rock on top should accomplish the desired objective. Especially since when rock is mixed and allowed to jiggle and settle, the bigger particles tend to sit on top while the finer ones settle out, or get squeezed together at the bottom. So just given grain size alone, the larger rocks will dominate the top layer.

Baja_Costero said:Adding fertilizer would be redundant if you're introducing organic matter when you amend the soil in the ground.

I was planning to just have 1/2 of the soil in there (that the landscapers brought a year ago) and 1/2 of the inorganic you suggested. So I don't exactly know how much organic matter there is in that soil...

OK, let me back up then, because I misunderstood. Try this:

50% native soil + 25% perlite/whatever + 25% bagged soil (cactus mix or whatever, mostly organic)

More perlite than that would only be useful for really rot-prone plants, or very clay-ey soil (which I think would be obvious if it were present). I'm a fan of putting new organic in the ground every time I install a succulent, and for you this makes sense too, especially if you're not sure how much there is in the native soil to start with. Compost does eventually turn to dust and go away, but perlite does not, so as time goes on the soil will have less and less compost in it, and be more and more rocky in proportion. As a starting point, the mix above should work for you.

Great, I'll do according to that formula.

Now, regarding the succulents that are too little to move to the ground before the fall, would you recommend putting several in the same pot? I was thinking of using a nice large pot and group them. Or will that not let them grow fast enough?

You can put them in the same pot, but that may make it difficult to separate them afterwards if they are placed too close.

Baja_Costero said:OK, let me back up then, because I misunderstood. Try this:

50% native soil + 25% perlite/whatever + 25% bagged soil (cactus mix or whatever, mostly organic)

Finally I found a store that carries pumice (Home Depot and Lowe's didn't!). Now, if you can help me with the conversions that'd be awesome, since I know in gardening there are more factors beyond pure math (like dry vs. wet).
I have estimated the top 10'' layer that I need to cover to be 1/2 cubic meter, so I'd need to buy only .125 cubic meters of pumice and .125 cubic meters of organic bagged soil. But of course, that is not how bags measure their contents. The place I found has 5 eight-quart bags. Can I take those quarts as the liquid quarts? If so, according to an online calculator, I would need 130 quarts... that seems like a lot! So I want to make sure if I need to convert to liquid quarts, imperial quarts, or something else

Yes, quarts are quarts, a unit of volume. Pretty close to a liter.

Just thinking about this based on my own experience, if I needed 125 liters (130 quarts) of pumice, then I would buy 5 bags of the brand that I usually get, which comes in 28-liter bags (about as much as the average adult human can lift without too much trouble). That sounds like about right for the space you're working with.

If you were to buy the 8-quart bags you mentioned (less than a third the size of mine) then yes you would need 130/8 = about 16 bags to do the job.

Done! We managed to finish the first area (corner) Saturday around midnight, before the rain came :)
Here's a picture of right now:
https://photos.app.goo.gl/77WY...
Why do you think? :)

We used a container to mix the 3 ingredients (native, pumice, and organic) in the proportions you gave me. We did not use anything specific for succulents, just regular (Amend, Organic Plus: https://photos.app.goo.gl/jxr9...), I hope that is OK.

Here's the quality of the native soil (well, you know, it is not really native, but what the landscapers brought us a year ago, which was supposed to be "pretty good soil for fruit trees") that to me felt a bit muddy, so that you judge:
https://photos.app.goo.gl/8ax7...
(when it's dry, like in the video, it doesn't look so, like when it's wet)

My rough estimate (.5 cubit meters of total area) seems to have been about right, only a bit over, as we used 6.5 bags of pumice/amend for that corner area, and I don't think the area remaining (https://photos.app.goo.gl/2t4u...) will need more than that amount. We'll see.

I'm just checking with you before I proceed with the planting

Sounds good to me. I can't see the images right now (server/network issue) but I will try again in a bit.

For some reason I can't see those images on my computer, but I can on my phone, so I took a close look, and it appears the existing soil was already heavily modified with pumice or some similar gravelly sized rock. I apologize if you showed this before and I didn't see it the first time. You definitely should be mixing more organic into the soil. I realize it's a huge hassle to dig out, mix, and pour back in, but I think the effort will be worth it down the road. You do very neat work.

My advice at this point would be to examine what 25% pumice in that Amend soil looks like, just visually, and then try to get the bed to look roughly the same. Maybe mix in roughly an equal volume of Amend? I thought the existing soil was devoid of rock. Right now I'd guess you have about 50% rock in what you prepared, just using the eyeball test. And that will work okay, but you'd have to water more often and probably the plants would not thrive quite as well, compared to soil that would hold more water and contain more nutrients. If you were growing really rot-sensitive plants or the existing soil was mostly clay, you might be good to go at this point with lots of rock in there, but I think you'll get better results if you reduce the relative amount.

So again, sorry for the confusion, but that first picture would suggest you might need to mix quite a bit more organic soil (the Amend product) into the ground. Or please correct me if my visual observations there are mistaken.

Hi there!
However, when I wet the soil, it is very muddy and takes a long time to drain down. Take a look at the third video I added after watering the soil (the part I used 50% of):
https://photos.app.goo.gl/76po...

Yes, I see exactly what you mean. It sort of turns to slush and holds on to the water. I'm wondering if the previous soil modification involved the incorporation of vermiculite, an inorganic additive that people sometimes put into soil to improve drainage, which usually has exactly the opposite effect. The soil does not seem release the water very easily. The moisture should pile up wherever you water, percolate for a bit, then settle out of the top layer within minutes, and exit the lower layers within hours. Is that the soil after modification or beforehand? Did you change anything after the first round of mixing in pumice and Amend?

This is not a problem that I have faced so I can only guess at how to deal with it. The solution to soil that holds onto water too long is typically two fold: mixing in a sharp, gritty aggregate to break it up, and elevating the surface of the planted area above the surrounding ground level so that gravity will work in your favor.

What I showed last was the "native" soil (before the 25% pumice and 25% organic), so I think what I had originally mixed may actually be fine (pure luck!). I have a "Johnson's hybrid" aloe and a kangaroo paw that I am thinking I could transplant first. They meet the criteria you gave me of being the biggest. What do you think? Any special tips for those?

I am thinking of surrounding them with some special mix I bought (https://www.amazon.com/dp/B06X3SXGZD/)

In the month since I've had them, both of them have grown new flowers. Here they are a week ago:
https://www.amazon.com/dp/B06X3SXGZD/