I'm hoping to get some information for creating rock garden soil, and possibly some ideas on plants for the area. I live in a river canyon, with rocks everywhere. I also have large boulders that either landed together, or were piled together, and I would love to create a rock garden area in and around some of those boulders. I have an endless supply of rocks to create nooks and crannies for plants, but I have an extreme shortage of soil to fill the areas in so that I can put plants in there.

I have some semps and sedums that I plan to move to these rock garden areas to begin with. This area is outside of the fenced in yard, and I'm overrun with deer out there, so anything planted has to be deer resistant. I have lots of iris growing out in this area, and the deer haven't touched the iris in 3 years, but I need something other than iris in the new rock garden area. Also, short plants will be much better for this area, since I don't want to obstruct my view.

I've successfully grown both semps and sedum in my yard, which oddly enough has very few rocks in comparison to outside of the fenced yard, but I'm really not positive on what is perfect for either of those in a rock garden setting. I amended the clay soil in my garden for the semps with a lot of large sand and small pebbles, and they seem to love it. I've also planted semps in potting soil in a very shallow whisky barrel, with maybe 3 inches of potting soil, and they've grown like crazy in there with almost no additional water given to them. The growth rate may be due to the fertilizer, but they have been blooming, so I'm not sure that it is actually a problem having the fertilizer mixed in. It also could just be that particular semp, which I can't remember the name of, grows like crazy wherever it is. I'm in zone 6b/7a in north central Idaho, with blazing hot summers at times (up to 116 degrees for a few days during a couple of summers in the last 7 years), and harsh winters at times (covered in solid ice for almost 3 months one winter), but it's usually a little more on the mild side in comparison. Last summer never got above 100, but it did stay in the upper 90s for a long while, and the occasional short stretch of low 100s is normal during summer. My property faces south, and there is zero shade in the area I want to plant, so plants need to be tough! It's also not in an area that will be easy to provide water to on a regular basis, though I will certainly do that until plants settle in and get established, and I can do that occasionally as needed. I do not want to have to be watering anything out there weekly though, as it's just way too much work for me, and I'll possibly run into a rattlesnake or two, which I'm not fond of doing.

Specifically, I need information on creating the proper soil mix for the plants. More than likely, I'll have to purchase whatever "soil" I can find at Home Depot or the farm and ranch store and amend it to fit my needs. I know they sell something called top soil, but it's basically steer manure that has no soil in it because it hasn't even composed. It's nasty stuff. They also sell Miracle Grow garden soil, which appears to be partly composed wood with slow release fertilizer mixed in. That stuff works fine mixed in with the native soil for a regular garden, but I don't think it would work for a rock garden, especially on its own. Maybe I'm wrong though? It would be great if that would work, because it's readily available where I live, but I have pretty much no native soil to mix with it. Yes, I have some in my yard in the form of mostly clay, but I'm not willing to dig a hole in my fenced in yard. There is probably a rock garden mix that is commercially available, but I've never seen one here. I do think that the garden soil/partially composted wood might be a little too rich for what I would eventually plant there anyways, especially since it contains fertilizer, but again, I could be wrong about that.

Any suggestions on what to do will be most appreciated! I have no idea what to do in order for this to be successful to any degree!

Hi Natalie...I amend regular potting soil with about equal amounts of chicken grit #2 and find this works well in my rock garden. Grit is basically small crushed rock and it provides excellent drainage. I pay about 11 dollars per 50 pound bag at the feed store.
Whatever soil you use, you need to make sure it drains freely. I have agaves and small cushion plants thriving in my garden with this soil mixture.

Thank you so much! That is a huge help! I have both of those items already, so it looks like I'll be moving plants sooner than I had hoped! I was really hoping that potting soil would work, since the semps are doing fantastic in it.

Natalie

Hi Natalie!
it's so good to 'see' you again!

For sure you should get some eriogonum--there are several low growing garden worthy types and it would be very happy there!

I'm presuming that's a pic of the area you want to plant in? obviously the iris are planted in soil...
You want to add soil to the rocks and essentially create some planting pockets within the rocky parts? is that the idea?

Hi Dirt!

It's great "seeing" you again too! Hope all has been well with you! I'm still madly in love with Idaho and haven't missed Utah for even a second! Just a little challenging growing things here that the critters will leave alone!

The picture is one spot where I'm planning on planting things. It's easy to make little "pots" in between the larger rocks, and I have moved a few semps and sedum to that pile. I've got piles like this all over the place, and I have a plan that may or may not work, depending on how naughty the deer are going to be. I love the deer, but they are deer, so no telling what they are thinking! They keep removing two semps that I planted out there and have left the other 5 or 6 alone. They aren't eating them, just moving them a few feet away. I replant them daily, so we'll see how long they want to play. I hope they wear out before I do! They have also munched on an Autumn Joy sedum, which was a surprise. It's tall enough to take some nibbles, and I have lots more I can move out there if they decide it's not tasty enough to bother with.

The iris aren't in much soil at all, and they are doing fantastic. I can barely get a shovel in the ground out there, and then I have to pick out a bunch of rocks just to try and find enough soil to cover the roots. I did have to add in a little purchased garden soil in a few places too. I'm shocked at how well they have done though! I moved a bunch out there three years ago and they are thriving even better than the ones in the actual garden, where there are little to no rocks. So, I'm moving a bunch more out there! Thankfully the deer have never eaten them or even tasted them that I can see, but they are enjoying stepping on the newly transplanted ones. Next year will be better because all of the natural grasses will have grown back by then. I just weed whacked it this year to make it easier on me.

I just took at look at the Eriogonum, and I might have some seed for that. I know I've got buckwheat seed, but I'm not sure if it's the same plant or not. I'm really glad you mentioned it because I've never known where to put the buckwheat. Me and my seed purchases! I also have some candytuft that will probably do good if I add enough of something for drainage. I haven't had any luck getting them to grow here yet, but I'll keep trying.

Here are the iris in the general area that the rock pile above is. It looked so pretty out there this year! Can't wait to see it next year!

Wow--that's fantastic, like irises gone wild

Well here's the good news--stop worrying about drainage!
Clearly, it's rocky out there, sloped, and has 'very little soil', that you have access to anyway, which necessarily means that you already have good drainage. If you ever get a ton of rain, have you ever seen any areas of standing water out there? ever?
I'm pretty sure any excess water, on the rare occasions you have that (I don't know, I'm just assuming you are in a relatively arid area up there?? how much precip do you get?), makes its way to the river pretty quickly, down thru the rocks and down the hill.
So, pretty much, you could use just about anything you can get your hands on to add on top of what little soil you have there to work with and be fine. As far as bagged products possibly being too rich...yeah, maybe for some things...but not for long since they'll 'wash away' fairly rapidly.

Of course, if you come across deep pockets of heavy clay, well then, that'd be a useful site to harvest from. Clay works really well in elevated crevices

Funny thing--yes, most plants prefer to have good drainage. They also prefer to receive water along with their good drainage. And certainly, when they are receiving a lot of water, good drainage is essential. Of course there is a plethora of info anywhere and everywhere you look espousing the virtues of good drainage. Assuming sufficient water. Yet not much help for the water challenged out there...providing plants with excellent drainage and insufficient water yields dead plants Having conducted a great many experiments along these lines, I have come to realize the value of clay

Dirt, as always, you gave me the giggles!

The annual rainfall amount here is about 23 inches, which is pretty good! There are lots of farms here, and the majority of them are dry farms that have no irrigation, and you can't do that without a decent amount of rain. It's also not really arid, especially compared to Utah. I do not miss the cracking skin that I had while living there! The humidity tonight is 47%, which isn't bad, but it's not dry. I have never seen puddles out there where the rocks are, but I do get them in the yard.

My property kind of contradicts itself. Some of it is so rocky that it's nearly impossible to get a shovel in the ground, and then there are three large fields and one small field that I could easily grow crops in. In fact, we did plant one of them as a pheasant food and habitat plot, and I don't think Mark even hit a rock while plowing it. The other fields are the same. The dirt in the yard is all clay, so it's probably all clay out in the fields. I've never dug a hole out there to look at it, so I'm just assuming that it's clay. I also don't want to dig any of it up! Actually, my biggest worry about digging holes around here is having a deer break a leg while running and not seeing it. That worries me. If I dig in the yard, the dogs take it as a challenge and try to prove that they can dig deeper and fling the dirt farther. Then I worry about me breaking a leg by falling in the hole.

So, clay. I kind of hate the stuff, but I know it's actually good stuff. I just hate digging in it. I do have nice flower gardens in the yard, and all of my daylilies are super happy here, but getting them all planted wasn't much fun! I honestly never considered it for a rock garden either. I haven't gotten to the crevis part of the project yet, but I'll take your advice and dig some up for that. At least it has a glue like quality to it, so it should stick where I put it! I did fill some "pots" in the rocks with the mix that cwalke suggested, and after a few days, nothing has died, so that's looking promising! I noticed today that I've got some sedum missing, but the semps were all home when I went out there, and they are looking happy enough. I also transplanted a Lewisia out there, and I hope it survives because I've had it stuck in a horrible planter for the last 3 years. I can't believe it didn't die in that thing, and it is in much better conditions now.

Before I forget, I need to mention that I'm not a purist when it comes to rock gardens! Whatever works is what I'm going with. It's not reserved for alpine plants! This is my rock garden, and I get to make my own rules, right?

I knew that iris preferred good drainage, but I didn't realize how much they really like it until I moved them out to that area. I watered them in when I planted them, and gave them a little bit more that first summer, but only once, and I've never watered them again. When we moved in, there was a huge clump of them laying on top of some rocks, and they were blooming, so that's what gave me the idea to move them to that area. Those are the dark purple iris in the picture. They weren't even in dirt on that rock pile, and they were blooming! That's my kind of plant! The previous owners moved out at the end of February, so I know for sure they weren't tossed out there that year while in bloom. I've actually lost several of them in the flower bed around the house due to very poor drainage, thanks to the clay. I knew nothing about iris when I planted them there, so it's my fault. I added a lot of little pebbles and some course sand to that area last month, and it's draining so much better now.

I think with the candytuft, I have been tossing the seeds out where the drainage wasn't nearly good enough. They want it dry from everything I've read, so I'm going to sprinkle some seeds around on the ground out there around the iris and hope for the best. I've tossed at least 5 million wildflower seeds around the property, and the only thing I've had any luck with is poppies, cornflower, and a few Love in a Mist. Even at that, I have to search to find just one growing out in the fields. I've still got 5 million seeds left, so I'll keep trying! Oh, and I've had great luck with another plant that I can never remember the name of! The pheasant crop field has tons of it growing. It's blue, and it's Lewis' something or other. Lewis' Blue Flax. I can never remember the name of that plant! I almost live on the Lewis & Clark trail, as they came down the river that I live above, and camped in this area a few days, so I enjoy growing plants that they put a name on.

I also understand that many plants prefer good drainage. I just need to find ones that require it, so that they'll have a better chance of surviving. I just don't have the time or the energy to be out there watering anything after they get established. I barely have the time and energy to take care of the plants in the yard. Anything outside the fence is basically on its own, and this area is outside the fence!

Hi, Natalie. 🌞💟🌿💃🌻💚☀️

Hi Debra!

I sure have thought about you a lot recently! Some of the iris that I've moved came from you! I hope you are doing well!

I am well, thank you. So glad to know you are okay.

Would you like more Irises? I have TONS of them I can share.

And now that I've become addicted to them I have tons to share too
Irises are awesome--at first I just started sticking little ones in the darndest places where special little rack garden plants had perished. Now I'm in grave danger of having an iris garden

I imagine someone/somemanys went to great lengths to pull the rocks out of your fields and pile them on the hill for you a long time ago, how nice!
I don't know what the secret is to getting overrun with seedlings of whatever goes to seed--probably something to do with the fact that I don't want a gazzillion volunteers more than anything
Keep trying. Lotsa stuff likes to germinate in the rocks and find a root-run between them. Maybe add some bagged stuff plus grit for a loose topping/keep the competition down/time it right with the rains...something...you'll get some to take.
Definitely, try your buckwheat out there...some salvias, penstemon, lavender, larkspur, dianthus, asters--these all self seed like mad for me in my rock gardens

lovemyhouse said:I am well, thank you. So glad to know you are okay.

Would you like more Irises? I have TONS of them I can share.

Debra, you don't have to ask twice! Thank you for the offer!

I've lost a few that you sent previously, though I haven't figured out why for sure, because the rest have thrived. Had a very bad winter here though, and I think that's when they gave up. I'll sent a tree mail in a bit!

dirtdorphins said:And now that I've become addicted to them I have tons to share too

I think I'm becoming an iris addict too. Okay, I KNOW I've become an iris addict!

I've grown iris for years. It started in Utah, and I loved how carefree they were. I loved everything about them really, but daylilies were more my thing. I still have a huge daylily obsession, but I finally said enough is enough, and stopped adding more! Well, for now anyways.

I brought a few iris with me from Utah, and I love that they bloom earlier than the daylilies. Debra was so sweet to share some with me, as did another friend here. That filled in all the extra room at the time, but I've made more room since then! Plus, I just looked out the window and it looks like I've got a field that is a couple of acres or more, and it has nothing growing in it but grass that I hate to mow! That means room for more iris, right?

Silly me just ordered a bunch online, too! What can I say other than they were on sale, and I need more! Dirt, if you have some to share, I'd be happy to take them off your hands! Just let me know what I owe you for them! Since about 60% of my property appears to be a rock garden, I can go crazy planting them now!

According to a neighbor who had lived here for over 50 years, my property was never farmed, so I'm not sure why anyone would have cleared the rocks out of the fields. The people we bought from said that this woman's son used to farm the property though. So, we asked him, and he said it has never been farmed. The house has only been here about 20 years, so I don't know what to think. I'm no longer going to question it though. I'm just happy that I have some land without rocks covering it!

Sadly, I noticed a few days ago that most of the iris here have leaf spot on them. I have no idea what to do about it, if anything. It's not horrible at this point and it didn't affect blooming at all, but I do need to look into it a little further to see if I need to treat it. I think spreading them out more will probably help some, since they were getting a little crowded. Hopefully if I can get this resolved, I can share some too! I would never send them on to someone else with that issue going on though.

I love iris!

What I give for some acres!!!
sending you a treemail...

Reply sent, Natalie.

Oooh, Dirt! If you had acres to play with, I'd have to get on a plane and come see what that artist's eye creates!