the new soil added.. will drain ...

roots need air .. BUT... if the part that is in the raised part.. drains... then they will often work their roots into the clay below ...

every plant you see.. offered for sale.. ball and burlap.. is grown in clay... else they could never make a ball to burlap ...

and back in theday.. all mail order roses.. were grown in clay ...

clay is a very nutritious soil ... the only issue with it.. is drainage.. but the peeps above have perfected such ...

your problem.. is you are fixating on one variable of clay.. draining.. and declaring it a nasty soil .... and.. you are trying to grow.. a plant that requires high water maintenance ... but the soil doesnt drain... in all reality.. you are the problem... lol .. as am i.. but lets not tell anyone... lol ...

make any sense...???

ken

I have a friend who raised all her beds about a foot, lined the edge with stones, filled the beds with good soil, and they look gorgeous - and so do her plants. I have my beds raised for the same reason, non-draining clay. They do look great and give your plants the chance to survive.

I just looked at my hosta photos from the Dallas Arboretum, hoping to find one that showed the beds. Unfortunately, I only have photos of hosta. I didn't do any long shots that show the beds.

The beds are raised, but they look like hills or short berms. The Crape Myrtles are on the top of the hill. The hosta are under them. They don't have any "sides". All is covered with mulch. Most of the hosta do well. It's a trial garden, so some do better than others, but, the design works well.

I wouldn't think you would have to go more than 6" high. To get it to settle to 6", you would probably have to do 10 or12 inches to start with. The roots will go where they go. The crown will be up out of the part that doesn't drain. The hosta will then take care of themselves.

bk

The link below is another approach

Here is a link that might be useful: Some raised beds

If you are considering raised beds, why not do a berm? I've always thought berms were an attractive way to display a garden at different heights. You have to watch out that you don't cover tree roots too deep and shut out the air.

Here's an example from a tour garden. All the gardens had this feel.

Paul

Wow, Paul, I am so much in favor of berms. Also swales if you have a high thing and want to make a dip in it.

I do not hesitate to raise the low side of my garden, which is the side that gets squishy when we have torrential rains. Water will flow downhill, and like in the rocky berm picture above this post, the plants at the bottom receive the water flowing downward. A slope automatically promotes good drainage because of gravity, if you think about it.

I'm sure that my garden with its more level playing field where I've raised that one side up to six inches will still have water flowing through it. I did not actually LEVEL it, but did use my cinder blocks to rather terrace the area. At one point in time, I thought it was a level space. It wasn't until I installed hosta "bleachers" that I noticed the definite slope toward my back fence. Correcting for this is what has taken me so long, and broken my back hauling compost/manure and mulch....AND cinder blocks and lumber. But we are getting there. Maybe in another 3 weeks if I don't weaken!

My DH does his veggies in raised beds. He also did some raised planting spaces for my huge philodendron selloums. And we did one in-ground raised bed for hosta along our driveway. You'd think we were sandy soil, but not so. It is clay. We are on a hump of clay which is why we are at the mighty high elevation of 22 feet above sealevel here, where all the surrounding area is between 3 and 13 feet above. They have mucky river bottom mud instead of the clay.

I also put down thick layers of newspaper between the "ground" and the soil used to make the raised bed. Once the compost worms get hold of the paper, they will sort of blend the top with the bottom and do good things for your garden.

I use shallow raised beds...about 6 inches of good soil (lots of pine bark). As has been said, you are keeping the crowns out of the muck. When the water hits the clay level, you get lateral drainage. You will also find that the clay underneath the raised portion will improve a great deal as its moisture level is held more constant and as the earthworms move in. For me, raised beds are a great way to go!

Steel, you're thinking just fine. You realize you're not sure about how the final product will be, so you're asking questions before you start the work. Sounds like smart thinking.

That's the way to do it.

Cheers,
Don B.

Well,here in the mountains,all I have is raised berms! All my hostas are planted on some kind of hill,and all I have IS clay soil,so it would work well. Go fer it! Phil