How can I landscape under/around a huge old maple tree?

your only option is to container plant based on your hardiness zone

You can start at a point under the tree where you can dig and plant. The key is to find a plant that can creep into the empty spots and make it look like it it's always been there. Small roots you can remove, but the larger ones will just have to be your borders for the plants.

I've had success with some of the groundcovers meant for shade and hostas. These plants tend to spread and their roots can better navigate the maple's roots.

I personally would box it in with long 2 by 4 but they come longer lengths and add hostas and much and problem solved📌🍁 rocks would be costly to choose very that much ground space unless you live near a river.

Hello, here are some pics with ideas.

Since the tree is so large, you should plant shade loving plants. I really like hostas. They come in so many sizes and color combinations. And they are easy to split and make new plants from.

The problem with boxing in a large maple tree with roots that you can see above the ground is that those roots will continue to grow and break up the timber making the box. Roxaneg's idea to start where you can dig and put in plants that love shade and hopefully will grow inward. It seems to me like a better solution. Plants like myrtle have shallow roots so you can basically start a single piece as close as you can to the tree and eventually it will grow outward and also fill in the inner space. Look for a neighbor who has some and put a circle of single pieces around the tree. Put some hostas around the inside of the drip line for height & interest. (Ask neighbors about those too. I got a small piece from a neighbor and every year I split the plant and now I have over 20 of them strategically placed) Myrtle can also be trimmed back if it starts to grow too far out. We have some around a birch tree that is 40 years old and it looks so pretty in the late spring when the flowers come out. Good luck!

That's true with almost all ground covers. Just trim them back on a regular basis. If they get too tight, dig some out. I did that for years in one spot because it saved me from buying plants for that section every year. The archangel looks so pretty. It will definitely bring color to y our spring garden. Good luck and have fun!

Best of luck!