A couple of weeks ago, we mentioned our landscaping project on the north side of Mt. Michelle to create more intricate planting pockets, while raising the planting heights significantly via the use of rock assisted berms.
Phase 2 of the project was to create a cut through on northwest side through a previously inaccessible bed. Phase 2 is now complete, and visitors can now traverse the new path, exiting into the northwest side of the Mt. Michelle waterfall. This path takes you under the large speckled-leaf loquat, Magnolia macclurei, and several large conifers, so be sure to look up as well as down.
Last week, Jeremy and his staff tackled phase 3 of the project, which was the two 50 degree slopes on the west side of Mt. Michelle. Despite being planted for some time, we had lost some soil due to runoff, and the plants were screaming for more compost, and we were screaming for more rock pockets.
In less than a week, Jeremy’s team stacked these new retaining planting walls, which provide hundreds of new planting pockets for small woodland treasures. Each is now filled with our garden compost mix as well as an array of small, little-known plants. Just remember, if you garden on flat ground and think you are out of planting space, the key is to learn to think like a Pythagorean…a² + b² = c²…go vertical.
You’ll be able to see these newly planted areas during our winter open house, although it will take a while for the plants to mature.
Will the berm on the tree smother the tree’s roots, or is most of the berm there large boulders? Or is providing about 50% roots undisturbed enough for the tree to continue flourishing?
We used a mix of 50% native soil and 50% compost, in which the trees will thrive, despite the fill. Also, our fill zone was a small percentage of the root zone.
Looking forward to visiting JLBG this weekend for your Winter Open House. I’m bringing my oldest daughter, Kim from Jacksonville, NC who has never visited before. I preordered 4 hellebores and plan to pick them up then. Thank you for opening your garden. Looks like it will be a spectacular weekend!
Indeed a lovely weekend for garden visitors!
I can’t imagine:
1: how you can raise the level of the soil around the bole of an existing tree without harming it, and:
2: how do you mitigate root intrusion from shrubs and trees into these raised perennial beds?
Great questions! First, despite virtually everything written about trees, you can indeed changed the soil levels rather dramatically around trees….if you know what you are doing. We have 1 pine tree in the gardens, where as an experiment, we raised the soil 3′ deep around the trunk…over 20 years ago, with no ill effect. They key is understanding which trees are tolerant and which aren’t…sorry, there isn’t a list. The other key is making sure the fill soil you use is well aerated (high amount of compost) with lots of active microbes. It also cannot ever become compacted. Also, understand where the tree roots are in relation to your fill zone. If the distance from the trunk to the outer branches is 20′, then the tree roots that pick up most of the moisture and nutrients are 20′ to 40′ from the trunk. The roots inside this zone are primarily for support. We would also never raise the entire area around a tree, but only in certain sections of the circumference. Root intrusion from trees into the upper planting zone for perennials happens with the subsoil is poorly prepared (i.e. it has poor aeration, poor microbial activity, and poor nutritional balance). Roots naturally want to grow downward, so it’s takes some rather poor condition for them to realize that the only possibility for survival is to reverse course and grow upwards. The key for success is proper soil preparation.
Wow! That is VERY useful information.
Thank you soooo much!