[ConfusedGardener]

I'm digging out lots and lots of heavy clay from my veg beds, and have been wondering what I can do with it. So I thought a good idea would be to make a mound of it, cover that with a thick layer of gravel, then rocks and soil to make a rockery. Could it work?

[fatcat1955]

Rockery plant's normally need good drainage, why not add plenty of compost/manure to the clay. It will break down. A good tip is to rough dig in the Autumn and let the rain/snow/frost break it up for you.

[ConfusedGardener]

Rockery plant's normally need good drainage

That's why I was thinking of adding a thick layer of gravel on top of the clay - thick enough that most of the water should drain away/down to the bottom of the rockery where I'm thinking of putting plants that don't mind a bit of water logging.

I'm really trying to kill two birds with one stone here. I need to dig the veg beds now, and since they are close to where I'm putting the rockery, I can just dump all the clay I dig out of them straight into the rockery (to form a base). At the same time, the veg beds I'm digging now only have a shallow layer of top soil, so I'll take the layer of top soil from where the rockery will go and use it to replace the clay from the veg beds.

I will definitely be digging in plenty of organic matter later in the year as there are plenty more beds that I'd like to dig, but my main problem now is that I only have a couple of beds dug and I want to get a few more vegetables going so that we have a good supply throughout this year. I'd like to have dug beds last autumn, but we only moved in late last year, and since then there was no real chance to dig due to other priorities and all the rain we've been having. Digging beds is slow work here also due to the clay (very deep in places) and parts of our land are full of rubbish. I also like to dig deep where ever possible.

I know I'm cutting a few corners here and there, but I can't see any other way to easily accomplish the tasks I'd like to accomplish this season. The list of jobs to do would stretch to a few pages long if I were to write them all down, but my main priorities now are to get a few beds dug and start composting - there's lots of material to compost, but I need compost now so I'm having to buy it for the moment.

So the rockery is basically an afterthought so I can save a little time, and hopefully end up with a nice garden feature as a bonus.

[bendipa]

That's why I was thinking of adding a thick layer of gravel on top of the clay - thick enough that most of the water should drain away/down to the bottom of the rockery where I'm thinking of putting plants that don't mind a bit of water logging

The worst thing you can do with alpines is allow them to become waterlogged unless you are thinking of just using aquatic plants.It's a waste of time and money if you buy alpines and plant in gravel sitting on clay.. The quick remedy is to obtain plenty of sharp sand (not builder's sand) and grit and work it into the clay until the soil mixture becomes lighter and  porous. Adding compost, leaf mould or peat to this mixture will also help but they are a supplement rather than forming the basic soil medium requirement.

[Trillium]

An easy way with alpines is to make rock clumps and fill the spaces with potting mix and grit for good drainage, and then plant the alpines in this. You don't have to shift the clay at all and the plants have the drainage they demand. And you have an attractive alpine setup.

[ConfusedGardener]

The worst thing you can do with alpines is allow them to become waterlogged unless you are thinking of just using aquatic plants.It's a waste of time and money if you buy alpines and plant in gravel sitting on clay..

Thanks for the input and advice bendipa.

The idea is to have alpines on top, with enough gravel/grit/sand between the rocks so that the water drains between the rocks - I'll be careful to leave channels so that the water can drain away. Lower down at ground level I won't have alpines. I'll pick plants that can stand a bit of water. I have some seeds from an old variety of geranium which I think might work - it's quite invasive so I'm hoping that surrounding it with rocks should keep it in check.

I'd like the rockery to be quite tall, but I want to use materials I have available to me here. I don't want to spend money on it if possible, apart from on a few alpines. I figure the clay would be much like the impermeable bedrock of a real mountain. It would be like a mountain built to scale, with the wet valley below with water loving plants, and the alpines higher up.

I'll definitely be working amendments into the beds (for veg that needs to be well drained) that have lots of clay, but there is so much (the clay goes down as far as I've been able to dig, which is about 4 feet, and there is only 6 inches of top soil on top), that I'll have to buy a lot of sand and gravel, which I don't want to do, so I'll have to dig some out. I think it'll make sense to use what I dig out to build up the rockery to a good height - I'm thinking at least 4 feet high. I'll also be throwing in some big blocks of concrete that have been dumped on another part of our land that I want to tidy up... if I can figure out how to drag them over to the rockery!


Trillium - Thanks for the tips. Your expertise is always much appreciated!


BTW - the reason I keep mentioning gravel, is that we have a builders yard next door to us which has a big pile of of the stuff, and I'm hoping to get hold of some for cheap! Perhaps it might be better to try and get hold of grit rather than gravel though? I'll see if I can get my hands on bulk sharp sand too - I already have a few sacks, but I'm going to use them for potting up plants.