I learned its not a good idea.The roots suck all the food and water fromthe ground and theres alot of roots.certain trees like black walnut,maple are really bad.The walnut is toxic to plants.Shade is a problem if they need light or sun

And it can deprive the tree's roots of air and water.

I have had a nice wildflower bed under a mature maple tree for 6 years now. As well as two wildflower/ regular buy at the store type plants, beds under large oak trees. The maple is the trickest. I have found that it can be alittle more work then a regular shade bed. The tree soaks up most of the water and food from the ground in the bed. I compinsate this by a soaker hose and a heathly two - four inches of well composted manure each spring and fall. I have found the worst thing is digging holes for new plantings, because of the invasive and tight knit roots of the maple tree. To me when it comes down to it if you want to take the time for an extra little care of the bed as well as trial and error with what plants can survive it go for it. My best advice would be if you want to make care free plantings under a mature tree go with hostas and daffodils. They can grow just about anywere. If you want a more substancial raised type bed, go with native plants. They can talk alot more of what a tree dishes out then commercially grown plants. After all most grow under trees in their natural settings. Vica does really well in mine as well as bachler's britches- a small white wild member of the bleeding heart family. Also trillums do well as long as you give them proper water, they like a good soaking every other day or so. I hope this helps. :)

It can bother or endanger the tree. Most trees don't like heavy coverage of their root zones and can be damaged or die if they are over-mulched or if dirt is dumped (a problem during construction).

Maples especially (Norway particularly), as other have mentioned, have tons of fine surface roots that grow up into beds, mulch etc.

Maybe you could do a dry-shade groundcover combined with containers?

If the bed isn't raised more than 3-4 inches it should be alright. But like everyone else has mentioned, the roots of the maple will be a problem.

I'm not a fan of the Norway maple. If it were my yard I would build a nice raised bed over the stump of the maple and grow sun loving plants! sorry :)

kato - ROFLMAO! I'm still laughing. My sentiments exactly! Seriously, I had several 40' - 70' maples in my yard and if I had the funds they would all go. We're down to three big ones, and at $250 to $600 a pop for removal it can get expensive. We've taken out 5 in the last 8 years when they've proven to be a hazard - dropping 200 lb branches, sitting too close to the house, (we had one fall ACROSS THE ROAD! and hit the neighbor's car) that sort of thing.

I've tried many things under the remaining maples, and here's what I've found: Hosta, blue fescue, hellebores (lenten rose), aegopodium (goutweed), and ferns all do well. Daylilies and groundcover roses do well near the edges, where the sun reaches under the canopy. I put the plants in while very young to disturb the roots as little as possible, and water every day for the first month until they're established. Then I use "soaker" hoses to water two hours a week, every week through September, even when it rains. Just when I think everything's established and I don't think I have to water any more we get a period of dry weather and everything wilts. Once that happens it takes weeks for it to recover with daily watering - the maple roots take their fill before giving it up to the remaining plants. Too much trouble? Maybe, but we're gardeners - we're nuts!

We have what I believe is a Norway maple outside my kitchen window. I would never have planted it, but it came with the house when we moved in over 30 years ago, and tolerated all the abuse our kids could give it when they were growing up, from being climbed to having swings tied to its branches. Additionally, its dark leaves absorb the worst of the heat of the summer sun...

But when the children grew up and left, all that was left under the tree was an area of bare hardpan.

Realizing grass would never grow there again due to the dense shade, I made a slightly raised bed under it, probably six or so years ago. I just outlined it with the little curved scalloped bricks, and dumped leaves my husband had raked up and bagged the previous fall into the delineated area. I dug up an overgrown patch of tough orange daylillies and put them all in there, and edged the whole thing with every hosta I could get my hands on. Someone sold some mayapples at a hospital event, and I put those in, too, with some Solomon's seal and a few ferns. I also made the horrible mistake of putting in one plant of Yellow Archangel. I then surrounded the chosen plants with purchased topsoil and anything else I could get my hands on--I had a few bags of even older leaves which had composted rather nicely--and then covered the whole sandwich with mulch.

Anyway, the whole area has remained covered, and is more interesting than a bare spot of ground would be. I put in a dead stump for scenic interest, and the area has a nice, woodsy effect, which goes well with the rest of my garden. The hostas aren't really flourishing, but they are surviving, and the Yellow Archangel has covered about half of the space, and is trying to extend into the lawn. The daylilies stopped blooming a few years ago, but might resume now that other trees have been trimmed up. The mayapples still come up, and the Solomon's seal is slowly spreading. I even have a small tree peony on one end that has occasionally flowered.

The tree still seem OK--I think the additional moisture retention of the bed has compensated for the initial difficulty the bed presented to the tree's roots, which by now, of course, have risen to the challenge by growing up into the bed. I've tried to plant a few other little things in there from time to time, but nothing else seems to take so far.

There is an art to what you are trying to accomplish. Here's a good article on the pros, cons, techniques, and what to expect. http://aggie-horticulture.tamu.edu/extension/ornamentals/protect/protect.html