Little Gem Magnolias planted too deep

[oscar_e_leon]

I oversee our Church garden and a few years ago we renovated our gardens, which included a hedge of 55 Little Gem Dwarf Magnolia trees along the front perimeter of our property. Unfortunately, the vast majority of them were planted too deep. We only found this out after the job was done and we had a professional arborist evaluate our site. The root flare was anywhere from 2-6 inches too deep, some as deep as 8 in. I had to excavate the dirt to reveal the root flares around all the trees. Now we have "wells" around most of the trees. I gradually have been removing some of the dirt around each well to try and level out the depth differences in the surrounding soil. I have also had to keep removing debris/mulch from filling back up in the wells so as to keep the root flare exposed.

We've had a couple arborists over the years suggest covering these wells with small river stones to keep debris out, and also to make it look kind of decent. One of our arborist consultants was indifferent to the idea and even leaned against it. We were advised not to fill the wells with mulch as this would keep too much moisture around the root flare and above the root flare, and eventually the mulch would decompose into dirt, and we're back to where we started. We recently decided to give the stones idea a try.

I've already covered about 8 tree wells with these stones ("pond pebbles", to be exact, average 2" in diameter ), with an average coverage diameter of about 1.75 ft (the trees vary in size but average around 8.5 ft tall and 4.5 ft wide).

Does anyone have any thoughts and/or suggestions on this? What alternatives do we have? It's definitely too late to dig up the trees and replant them at proper height. They've been in the ground for about 2.5 years. I've included a couple photos.

 

[ATH]

How impractical is it to regrade the surrounding soil to level with the trees? Call the company that planted them and ask for suggestions to repair their substandard work...

Lifting them isn't impossible...if you think that is the answer sooner rather than later will be best.

I agree, no mulch. Stones are OK, but over the years leaves and debris will accumulate in those as well. Of course over the years somebody will also stop carit and cleaning out the litter that accumulates under there if you keep them open... I'd probably opt for stones as you described.

 

[oscar_e_leon]

How impractical is it to regrade the surrounding soil to level with the trees? Call the company that planted them and ask for suggestions to repair their substandard work...

Lifting them isn't impossible...if you think that is the answer sooner rather than later will be best.

I agree, no mulch. Stones are OK, but over the years leaves and debris will accumulate in those as well. Of course over the years somebody will also stop carit and cleaning out the litter that accumulates under there if you keep them open... I'd probably opt for stones as you described.

The issue with regrading the surrounding soil is that we have Creme de Menthes planted along the front of the trees, at the soil level that the trees were originally planted :/ There is already a bit of a "rolling hills" kind of look around some of the trees. I suppose another option is to remove the Creme de Menthes, regrade the soil, and then replant the Creme de Menthes? Another challenge is that there is lawn in front of a set of 8 trees, ground cover in front of another set, and a rose garden in front of another set. I think regrading the soil around the Magnolias would make it look like they are on a downhill along our perimeter wall. I've included a couple more photos.

Lifting and replanting nearly 50 trees is beyond our scope at this point.

Some of the stones, in the wells that I filled, needed to come up to a level above the root flare in order to level out with the surrounding soil. Is this ok? Any potential damage to the tree base/bark? I'm in Los Angeles, by the way.

 

[Jason Douglas]

I've used pea gravel, no limestone, in the depressed area and river stone on top as a more ornamentel top dress to cover up the pea gravel

 

[ATH]

Yeah...would look odd to change grade with the wall there.

I'd probably do rocks like you have keeping them level, not mounded higher than grade.

 

[Jason Douglas]

Here's a deep hybrid maple we did but before we put down river stone

 

[oscar_e_leon]

Yeah...would look odd to change grade with the wall there.

I'd probably do rocks like you have keeping them level, not mounded higher than grade.

Thanks. Looks like we'll be going that route.

 

[oscar_e_leon]

Here's a deep hybrid maple we did but before we put down river stone

Ah ok. Glad to see another example! Many thanks.