Even if you’ve never heard of “underplanting,” you have probably felt the need for it. Most of us have a tree under which grass fails to grow. We have only bare dirt or weeds in those places, but is there another option?
Well, we could spread a shredded bark or pine needle mulch.
But is there a more interesting option?
There is, and it’s called underplanting.
You’ve probably seen trees or shrubs underplanted with pachysandra or ivy. Neither one is especially interesting to look at, and ivy can be invasive. Better options for these shady areas are hostas, ferns, and ephemeral spring-blooming bulbs. The spring flowers will fill in the space before any perennials grow up and get going. If the soil beneath your tree is especially dry, epimediums might be a good choice.
Here are some tips to keep in mind before you plant:
- Don’t plant only out around the dripline of the tree. You want to fill in the space underneath the limbs, getting as close to the trunk as you can.
- However, you can seriously damage a tree digging around near its roots. It won’t be possible or advisable to plant regular nursery-sized perennials. Try planting small divisions from your own garden plants, small perennials purchased from a nursery, or order “liners” from your landscaper or nursery. These are small plants available from wholesale growers that haven’t yet been potted up and grown large for the general plant-buying public.
- Tools: no shovels or tillers. Instead, use a small hand trowel or a digging knife, often called a hori hori.
The garden writer Margaret Roach has wonderful advice about underplanting trees in our gardens. Look for her blog or the wonderful new edition of her book A Way to Garden: A Hands-on Primer For Every Season.