May I suggest that you try adding a couple layers of Composted Cowmanure and Just plain Compost??..That is what I do every Spring to refortify my flowerbeds...the plants will love the nutrients from this and also..keep your plants more moist!!!...Like Mike said Clematis need to be planted 2-4 inches deeper than the pots you get them in to aid in the roots staying moist...and mulching helps..but keep the mulch away from the vines...Jeanne

Another good point, bboy. Although they'd need less watering than if transplanted, I suppose, their roots being left intact... Ken, I'm making raised beds because my property is dead flat and I needed some contour and elevation changes for a variety of reasons. I'm basically putting a row of boulders together, somewhat artfully I like to think, and filling the resulting enclosure with soil. I'm not sure a photo now would say much, as (a) there are still as many rocks lying around as are already set up, and (b) it is cherry blossom season and my street tree has blanketed my yard with pink petals; it looks odd to say the least. But I'll try later. I think the bottom line is whether or not I'm willing to risk these particular plants, or perhaps more accurately, which risk I can best mitigate; the effect of covering the roots or the effect of transplanting them. The yew is not so much an issue, but the Chamae would be a shame; it's just a little obtusa nana aurea, but has at least five years of growth on and is quite pretty. Will see if I can find a presentable section to photograph later. KarinL

I've never done it, but if I wanted to I would put some sort of collar around the shrubs. 3 - 4 inches out, and then go ahead and add soil. That way, they won't rot at the base of the trunk. Suppose you could use some kind of PVC pipe that you could cut and then fit around the trunk. Have you ever seen those concrete tree collars? They come in half circles. That might work.

laurietennant: clearly you want to keep the existing hibiscus, so I think the tree well is worth a try. How it looks is a matter of personal taste. You do need to allow for sufficient space around the trunk. It would also help if the depth you're planning to add were reduced. Do you really need a full meter or would half of that or even less be enough for what you would like to plant in the terraced areas? (That's assuming the terraces will be for plants. If instead this is more a landscaping project with a full meter necessary to do what you want, much changes). A half meter or less over some of the hibiscus roots will not drown them or smother them if you use coarse fast draining material like bark or bark compost mixture with or without grit or sand. Do not use soil. It is too dense and not porous enough to allow oxygen to reach the root zone.