Shop Products
Houzz Logo Print
amcbride_gw

How can I convert my clay slope into a REAL rock garden??

amcbride
21 years ago

I inherited a wonderful spot for a rock garden when I bought my house a few years back. I immediately added tufa, alpines, some gravel, etc.., and have more or less treated it as a rock garden. Problem is that it is a slope with about 10 feet of clay as the bed. I can't afford, nor have the strength of back, to dig it all out and re-do it 'correctly' like scree or sand, etc.. I have ideas about digging holes with a large drill bit, and just keep filling them with sand and such to over the years loosen the soil (I can't dig big holes because gorgeous tulips, frittilarias, etc.. all dug in). The garden does 'okay', but isn't optimal I know. Any ideas on how to improve without starting from total scratch? The link here shows some shots of the area to give you an idea..click on the thumbnails for best view. (Alot of the alpines are covered over by the ferns and such that are thriving in this area!)

Here is a link that might be useful: Rock Garden and other landscape pics

Comments (7)

  • pondwelr
    21 years ago

    Your gardens look wonderful to me. Surely you are not complaining about the fertility of the clay base. The idea of gradually adding rock and sand cover is the best, because like any mulch, it will eventually be the top layer. Getting deeper and better all the time. Clay really is fertile, tho difficult to deal with for farmers.

  • amcbride
    Original Author
    21 years ago

    Thanks for the reply; I think my concern is how compacted the clay is, not the fertility issue. I have been concerned about the drainage, but, being on a slope, that isn't too bad an issue when I really think about it logically! I will keep up with the sand and pebbles and hope for more 'pliable' dirt in the years to come.

  • sbeuerlein
    21 years ago

    Adding sand to clay can actually worsen compaction. It can harden soil up really bad. Be careful not to work it in too deeply. Keep it mostly on top. But, truthfully, unless you are determined to grow really difficult alpines, I would leave well enough alone and enjoy what you've got. It looks beautiful. Remember the old adage, if it ain't broke, don't fix it.

    Scott

  • amcbride
    Original Author
    21 years ago

    Thanks again for the advice..I knew sand could further compact the soil, but keep hearing different stories on this. I will leave well enough alone as you both advise, and keep doing the little bits that I can.

    thx!

  • kenc_co
    21 years ago

    I live in an area (nr. Denver, Colorado and the foothills of the Rocky Mountains) where the soil is bentonite clay (very alkaline, easily compacted, and a challenge (to say the least)) for gardening. The soil is fertile, the trick is how to make the plant nutrients available to the plants you grow. One solution is to mulch with lots of humus, composted manures, ground bark, and any other good organic material. It seems to work for most local gardeners. I never plant anything (well, except for maybe a few native plants) without adding a good 1/3 of some sort of compost to the planting hole or flower bed. Most of my gardens are rock gardens and the one in the front of the house is a steep, narrow slope (facing northward). Another idea is to use a good reference source to find plants well-suited to your clay soils.

  • MayBATL
    19 years ago

    My main concern after looking at the great pictures and reading the recommendations is that I need to make it easier to move up and down the hill where I plan to have my rock garden. I am afraid to fall and hurt myself... lately between the heat and humidity, poison oak and english ivy, I am so tired all the time and so frustrated because, as I said, it is quite steep and I am no spring chicken. amcbride's garden took my breath away... perhaps I need to work on being more patient and quit trying to get it all done right away. It will tell me what to do.. it is already doing so because I realize it is not safe for me to be up there with nothing to hang onto or not having good solid footing under me.
    May in Atlanta, Ga

  • calliope
    19 years ago

    I garden in Ohio clay as well. As stated, it is extremely fertile and if you think about it, this state abounds in its lushness and green. Clay isn't all bad. The fact your rock garden is on a slope is your ace in the hole. I don't care how compact and course clay seems, the drainage issue is solved. It drains!

    Being in the Appalachian foothills, I can say that there really aren't many level areas on my property and the area in which we installed our rockery is rather steep. It was the dumping area for coal ash and cinder from the furnace and it is also underlain with a spring or two. What was once the problem area of the landscape is now a rock garden, because we knew that was a good way to utilise all the qualities of this area and turn those sows' ears into silk purses. I love how it lends itself to a rockery. Some of the clay soil even gives way to grey horse shoe court material. You could throw pots from it.

    Of course the major thing to remember with clay soil is to wait the magic number of days after a rain when it has reached the optimum level for digging. Too soon and it is slime and too late and it is concrete. It is hard to be that patient, but hey it develops character in a gardener. Then choose your plant material wisely. Some plants actually do just fine in dense, clay soil and prefer it over the soft, friable and moist loamy stuff where they get too soft and leggy and lank. Good Luck!

Sponsored