Looking for advice, tips and tricks on the construction of a mini mountain rock garden with height.

Parameters:

1) It'll be a one person job; I can lift and set real stones to 50 pounds per, but if a portion of it can be made of lighter man-made materials I'm all for it. Could hypertufa be incorporated in the design?

2) Sans machinery to lift, dump or carry. All off-site materials will be personally handled by me, and ferried home with a large truck and small trailer.

3) Prefer a fairly natural look when finished, in all four seasons; one of which suffers negative number temps.

4) Variable heights, with planting crevices from bottom to top.


Musings:

I can do a mortar and rock wall type of thing, but I'm not too sure that I'll be fond of the non-natural form.

I really like the look of slate, but will using it allow for a cohesive design if I'm also using field rock and/or faux rock?

I'm thinking that a dry wall stack using slate for the height might be my best bet. If so, how deep does the earthworm gravel barrier need to be, or would I need it at all for a flat stack?

What do you think? Any tips toward answering these questions will be greatly appreciated.

Here's a starter list of what I'd like to try to grow in and around my future rock garden.

Campanula coriacea
Campanula rotundifolia
Keckiella cordifolia
Lewisia rediviva
Michauxia campanuloides
Mimulus cusickii
Mimulus aurantiacus
Mimulus palmeri
Minuartia laricifolia
Musineon tenuifolium
Nama rothrockii
Penstemon albidus
Penstemon cusickii
Pulsatilla vulgaris
Ramonda myconi
Rhodiola integrifolia
Stachys lavandulifolia

...and lots of others.

At my old house I reworked the 8 feet of front yard. It wasnt worth mowing.
This is a dry stack wall with no barrier under peagravel. Pea gravel was about4-5 inches deep.
If I had it to do again I would use a barrier.After 10 years the pea gravel submerged in spots.
August 2006


2005 May

Don't forget the sempervivum and sedum!!!

Quoted from here The thread "Rock Gardens" in Rock Gardens forum

dirtdorphins said:I'm gonna have to say that a lot depends on the plants that you wish to grow then and the all-rock substrate that you wish to use.
Sorry, having a little confusion replying here to Q's in the other thread as well--
Yes, of course, you can incorporate hypertufa into the design--if you can make it or get it--and plants can actually grow right in the real thing or the fake thing, but they will not grow right in field stone, for example. well, okay maybe some mosses, algae and lichens will, but I presumed that is not quite what you had in mind. Slate, in my experience, depends on how flaky it is really, but there the plants/roots are growing in the crevices between flakes not actually in the rock, or roots are behind the rock in the medium in the case of a dry-stack-wall. Some lava stones and some sand stones, with 'built in' crevices have worked pretty well for me with some weeds.

Thanks, DD.

I imagined that I'd leave cracks between the slate slabs as a place for my transplants' roots to travel. The rest of the flat surface that isn't covered by growth could then be used as a place to step in the bed to reach the center-most plants. So, maybe something that's similar to a dry stacked wall with some additional hypertufa pieces arranged in the center? Hmmm....that might actually be pretty neat; dark grey stone at the bottom, with the contrast of the lighter hypertufa in the middle...thinking on it.

Love it!!!

looks like you want a little CA in IN--
I'll check back later because I've really got to go now

dirtdorphins said:looks like you want a little CA in IN--
I'll check back later because I've really got to go now

Yup. I figure if we're not ever going to get summer rain again, I might just as well plant things that don't require it. I'm ever-so tired of the water battles!

Sylvia,

Do you grow in a rock garden? I'll be kicking this plan around for the entirety of our long garden-free winter, so if you have experiences to share I'm all .

Well,
I was hoping some folks who actually know what they are talking about would have some useful suggestions for you by now.

I am so not an expert, or personally familiar with all the plants on your list...but looks to me that none of them absolutely require special rocks for their happiness, as in they could grow in a well drained scree just fine, which allows you a great deal of freedom in design and execution.

What rock material do you have available?
Is the mini-mountain for drainage or aesthetics or both?
How is your drainage? do I recall some seasonal flooding lake or something or am I getting people's places mixed up?
maybe its just my luck, but it occurs to me that as soon as you succeed with summer drought tolerant plants the rains could return...

How's your humidity--some plants that flourish in lean summer-dry soil in arid environments will literally melt in high humidity. (for example, Stachys lavandulifolia, or so I have read. I don't know about IN, but I used to live in MN and recall miserably humid summers. I planted one here this year, did great--I love it...but I never tried one in MN. I did have the monster byzantina at the MN farm, out on the badly neglected, wind tunnel, boulder pile, never watered--tough as nails, but even it had some issues with the humidity. I use byzantina here on the 'north 40' for erosion control on a steep drop to the road with no summer humidity evils, because this is a desert.)

Anyway--I have never grown mimulus because I don't think they could survive my winters, but I have a lot of penstemon, a few pulsatilla, and campanula...and a bunch of other stuff not on your list.

For me, here, on this part of the mountain, drainage is a key issue because I have serious clay that doesn't drain when it gets wet and it wont get wet (runoff) when it gets too dry. It is rare for me to see a worm so I don't really understand what the worm problem is. I have had to incorporate a lot of grit and organic matter just to grow anything, so that water can get in as well as move out. And in the areas where I have done that, things work pretty well. Plus, and, raising beds and using hills.
Still though, providing water--especially to establishing plants--can be a challenge. I have also erred on the extreme side and tried to plant some precious little things that demanded so called perfect drainage in pure sand/gravel and killed them because I failed to provide sufficient 'thunderstorms' during the epic heatwave--whereas same/similar plants in a soil mix survived. Go figure.

Winter is only just getting started...
I gotta go to bed

chelle said:
...mortar and rock wall... but I'm not too sure that I'll be fond of the non-natural form.
...slate, but...also using field rock and/or faux rock?
...a dry wall stack using slate for the height might be my best bet. If so, how deep does the earthworm gravel barrier need to be, or would I need it at all for a flat stack?

I wouldn't suggest a mortared rock wall unless you actually have a use for one. If the wall idea is just to create height, making it in a dry pack style would allow the wall itself to be planted though. But it sounds to me like what you really want is to create something that looks reasonably like a natural outcrop (unless I'm misinterpreting), so why not go for that?
I think a mix of rock type could certainly be made to look good; it would take more thought though.
I'm not familiar with the concept of an "earthworm barrier" so couldn't say.
I'll post some references on rock garden construction later...

dirtdorphins said:
What rock material do you have available?

I can gather plenty of local field stone. Some of our other garden areas also incorporate slate or shale type flat rock for steppers, and crushed limestone for soil coverings, but those I have to bring in.

dirtdorphins said:
Is the mini-mountain for drainage or aesthetics or both?

The ideas behind the mini-mountain are:

Improved drainage in a new bed (all the rest are filled to overflowing)
Added height to improve air circulation (to help control rot)
Overhanging shelves of rock to help keep the most moisture-susceptible crowns dry
Crevices, also for proper moisture levels (the crowns can't sink too deeply and rot)
Added height so that my poor vision isn't such an issue in viewing the tiniest plants

dirtdorphins said:
How is your drainage? do I recall some seasonal flooding lake or something or am I getting people's places mixed up?

Yes, we're on clay, and the center of our yard is a natural pathway for storm water runoff; the moisture-lovers like it there. Most of the rest of the yard is comprised of gentle slopes.

dirtdorphins said:
How's your humidity--some plants that flourish in lean summer-dry soil in arid environments will literally melt in high humidity. (for example, Stachys lavandulifolia, or so I have read. I don't know about IN, but I used to live in MN and recall miserably humid summers.

We can have high humidity, but not so much in the past several years. I'm assuming that's due to the fact that we're in a tiny pocket that gets no rain after mid-June. Most of the summer there's a southwesterly breeze coming off the lake, and right through the area that I plan to use. The Stachys lavandulifolia may have to reside on our south-facing, covered porch where there's a ceiling fan that can be used to stir the air. There's going to be a lot of trial and error going on, as I've never tried these types of plants here before.


I'm planning at least two different methods for each of these plantings; one in rock, and one in standard raised beds that (so far) have provided excellent drainage for regular garden plants...just to see.
I have some Lewisia overwintering in one of those now. I'll be interested to see if it survives. If it does, I may not need as many rock beds/planting areas as I'm thinking I might.

growitall said:

I wouldn't suggest a mortared rock wall unless you actually have a use for one. If the wall idea is just to create height, making it in a dry pack style would allow the wall itself to be planted though. But it sounds to me like what you really want is to create something that looks reasonably like a natural outcrop (unless I'm misinterpreting), so why not go for that?
I think a mix of rock type could certainly be made to look good; it would take more thought though.
I'm not familiar with the concept of an "earthworm barrier" so couldn't say.
I'll post some references on rock garden construction later...

Thank you! I'll be looking forward to it.

From what I understand, the barrier is supposed to keep earthworms from bringing up native soil and excessive nutrients and mixing them into the planting areas of plants that won't appreciate it. Totally different idea compared to other garden areas where hungry plants live, right?

growitall said:

It's sort of complicated (but fortunately, growing some desirable plants isn't ) and I'm no expert, but it's probably safe to say that for most rock garden/alpine plants, it's really the soil conditions (primarily drainage) that are important, not the presence of rocks per se.
The wetter/more humid your climate, and the more prone it is to winter wet especially, the more important drainage becomes (hence the popularity in wet areas of alpine houses - the purpose of which is usually not insulation but primarily to shelter plants from too much water!)
As shown, sand beds and gravel beds can be great for growing plants that need good drainage and lean conditions - no rocks are required at all... in fact, to be honest, unless rocks are used skillfully, as in the incredible crevice beds I showed, they can actually reduce one's planting space quite a bit.... they take up a lot of room! However, the presence of rocks allows one to create structure and build up the garden (elevating it above the surrounding area improves drainage), and some rock garden/alpine plants do like to grow best with their roots in deep crevices between rocks. As you noted, rocks also allow one to create shade and shelter. And I suppose they help people to identify it as "a rock garden"... and I just like rocks, as many of you have said too!


The tufa is all natural, bought from Rocky Mountain Tufa whose quarry is in B.C.. The rocks were basically manhandled into place (we did it all ourselves with no machinery - DH had to move the biggest pieces from the first big order that were beyond my abilities; I avoided really big rocks in the second order!) The tufa rocks were mostly place on end for height. The main thing was the process of packing a lean soil mix in between the rocks, to stabilize them all and provide the growing medium and the fill in crevices. I'll post some photos of the process.
Keep in mind that I'm not saying this is the best or only way of doing it - it's only how I did it.

Well said!!!

For me, the winter wet issue is really a spring wet issue--when it actually rains and all the snow melts and everything gets soggy. And when the ground is still frozen beneath the first few inches then we can get some serious sog. For example, delospermas survive the winter well for me but die in the spring if I plant them in my crappy clay. Conversely, in elevated free-draining areas, they do well.

chelle said:

The Stachys lavandulifolia may have to reside on our south-facing, covered porch where there's a ceiling fan that can be used to stir the air. There's going to be a lot of trial and error going on, as I've never tried these types of plants here before.

Re: humidity
Air circulation is indispensable, but a ceiling fan stirring the air does nothing to decrease the relative humidity. Big difference between 20% and 80% no matter how much you move it around.
That being said--why not try it where you want it out in the open rather than a covered porch with a fan? Who knows--it might be just fine. Mine is not tiny, btw--it made a nice mat about 5"x16" as soon as it settled in

dirtdorphins said:

Re: humidity
Air circulation is indispensable, but a ceiling fan stirring the air does nothing to decrease the relative humidity. Big difference between 20% and 80% no matter how much you move it around.
That being said--why not try it where you want it out in the open rather than a covered porch with a fan? Who knows--it might be just fine. Mine is not tiny, btw--it made a nice mat about 5"x16" as soon as it settled in

Thanks! I'll do that.

New topic, same forum ... Seeds vs. Transplants?

chelle said:Here's a starter list of what I'd like to try to grow in and around my future rock garden.

Campanula coriacea
Campanula rotundifolia
Keckiella cordifolia
Lewisia rediviva
Michauxia campanuloides
Mimulus cusickii
Mimulus aurantiacus
Mimulus palmeri
Minuartia laricifolia
Musineon tenuifolium
Nama rothrockii
Penstemon albidus
Penstemon cusickii
Pulsatilla vulgaris
Ramonda myconi
Rhodiola integrifolia
Stachys lavandulifolia

...and lots of others.

My thoughts....
Unless you've found that you can't grow Campanula rotundifolia in your regular beds, I personally wouldn't tend to use my precious rock garden space for it (and you have indicated that there are lots of other species you're interested in). Yes, it does occur in the lower alpine zone here (through to the prairie grasslands) but it doesn't require any special conditions in my experience (THOUGH with the previous proviso). There are many other exquisite alpine Campanula species that I would save the rock garden space for. Having said that, I haven't yet grown C. coriacea, though Campanula species are a favourite of mine. Take pains to avoid the invasive ones though... Again, with the same line of reasoning, rapid spreaders like C. cochlearifolia and similar are best left in the regular garden.
Rhodiola integrifolia is not much in cultivation so you may have trouble finding plants or seed. Rhodiola species in general though are pretty easy to grow in the rock garden and you may find other species a lot more easily.
I found Stachys lavandulifolia to be too invasive for my tastes. Had it been a lot more freely blooming, I might have felt otherwise, but I yanked it after 2-3 years.
Just my experiences... yours may be different in your area.

Thanks for the tips! I have Rhodiola integrifolia seeds on order, but no confirmation on availability as of yet.

I'm so happy to be gaining this additional knowledge, and the fact that I can come back to it at planting time and double check things is going to be so awesome!

Forgive me, I am going back to rocks for a minute, even if they take up too much room--I think we have established that I like 'em! especially big colorful ones, but not limited to that. I would totally make tufa mountains if I could get some...and believe me, I hunt the prehistoric lakeshores and pick up every scrap that I can.

One of the pics I showed before is actually a mound on top of a gnarly tree stump (that I couldn't take out) within a raised bed between two concrete walls. Here's a slightly closer look

These are all 'found' rocks that I picked up and put in here not once but twice (and not as good the second time--ran out of vacation) because I redid the mix with more grit. I love the swirly fossil and someday I am going to grow somethings in the pockets of the monster face one. Is it a stellar design for the cover of anything? NO, but the illustration is that you can make a mini mountain with "whatever" rocks. The backside is planted too with those that need some shade, but I could have built the mound against the wall.

Here is another less than stellar step system using pine tree roots (w/ volunteer alyssum) and random rock into ...an overgrown pathway...


My first experiment is actually on the backside of a large boulder, and sorry I don't have a decent picture of it. Those that follow are all cropped out of the corners of other pictures and have poor resolution.
Here, though, is a super cute and very tiny flower of one of the plants that lives there, bear with me...


The rockpile is in the grave garden. There used to be a big sage behind the big rock and some other stuff. I pulled it all out and made a raised 'pocket', so to speak, of sand/gravel over smallish rocks in the bottom. The sides are held in --sort of-- with some spare pieces of decayed concrete (everyone has those right? well, I do) and then I put some rocks around it (because I have a lot of those, too) so it doesn't look like the concrete garbage that it is. There is also some sand/gravel spilling out of the front and around the side crevice.
Here is the grave garden in early spring and you can see the rockpile. (The beloved dogs are a good 6' under the cherry tree and evergreen)



Here is a pic of the backside and some corners of other shots. There is actually a plant growing under the overhang (in the hole, but it is too protected from light and moisture)




Rather unconventional I suppose, but again, the illustration is that you can try some different things, with all your seedlings of course.
Here is a broken shale with plantings--you could essentially make a broken 'rock' with shale pieces--and a couple cuties, with little rocks, on the scree slope