donnan.com

Shop our Lawn & Garden Store
Sales help support this website!

 

Groundcover grown under Trees

Groundcovers that will do better than grass

By: Sandy Feather ©2011
Penn State Extension


Q. I have a sweetgum tree in my front yard that appears to be healthy, however it is beginning to leave a large circle of dry soil/grass around the circumference of its roots.  Do you have any suggestions to prevent or minimize this? 

A. Sweetgums (Liquidambar styraciflua), Maples and other trees tend to have shallow root systems that compete fiercely with the lawn for water and nutrients. Other trees that tend to have shallow root systems include maple (Acer spp.), beech (Fagus spp.), honeylocust (Gleditsia triacanthos var. inermis), linden (Tilia spp.) and elm (Ulmus spp.). It is not surprising that the grass is thin and struggling to hold its own under this tree.

As time goes on, I expect the sweetgum’s lateral roots will expand up to the soil surface and make mowing a misery for you and the tree. While you can cover these roots with soil and plant grass seed, that is not healthy for the tree in the long run. And it will have to be re-done periodically as the roots grow, creating a never-ending chore for you. 


Groundcover instead of Grass

It will be easier on you and the sweetgum if you are willing to replace the struggling grass with a ground cover that is tough enough to compete with the tree. It prevents you from wounding the tree roots with the lawn mower, which creates an entrance for insect and disease problems. You will not have to replace the mower blade as often, either! It is ideal if the ground cover bed extends out to the dripline (ends of branches), but even half the distance to the dripline is good.


Pachysandra around a Pin Oak


Do not Rototill

Although good soil preparation is key to getting ground covers off to a good start, it is not a good idea to rototill in the root zone of established trees. Carefully choosing tough plants that you can plant around the sweetgum’s roots without working up the soil is best. Simply create a hole about twice the size of the ground cover plant’s root ball and install the plant. Finish by watering well and mulching with an inch or two of shredded bark or wood chips. If the existing soil is truly horrible, you can work some compost into the top couple of inches of soil and plant into that.

Be sure to plant whatever ground cover you choose in staggered rows, as if you were laying bricks. If you plant them in straight lines they will take longer to fill in the area.


 


Brief list of ground covers that should tolerate life under a sweetgum tree:

Green and Gold (Chrysogonum virginianum) – This native, semi-evergreen ground cover grows six to eight inches tall with a comparable spread. Plants start out as softly rounded clumps, gradually growing together to fill the area. It blooms with gold, star-shaped flowers in spring, then sporadically through the summer. Tolerates sun to partial shade and range of soil types as long as drainage is good.

Bishop’s Hat  (Epimedium spp.) – Also known as barrenwort, Epimediums are more tolerant of dry shade than most plants once established. They spread slowly on underground stems known as rhizomes and bloom in spring with racemes of flowers in shades of yellow, red, lavender and white. The new growth of many species starts out with a blush of red in spring, and then hardens off to green. Bishop’s hat grows one to one-and-a-half feet tall.

Hosta (Hosta sp.) – Hostas come in all sizes and colors, from very tiny rock garden favorites to large, bold-leaved specimens. Leaves range from plain green to yellow, to white or yellow variegated to deep, textural blue. They are tough, durable plants (except for their susceptibility to deer damage!) and tolerate competition from trees in stride. Well known as shade plants, all need shade from the heat of the day, especially gold-foliaged varieties.

Hosta
Hosta comes in varied colors

Lily-turf (Liriope muscari or L. spicata) – This evergreen, grass-like plant is grown for its dark green leaves. It grows about a foot tall with a similar spread and blooms in late summer with a spike of lavender or white flowers. Gold and white-variegated cultivars are also available. This is a tough, durable plant that tolerates sun to deep shade, road salt, and variety of soil conditions as long as drainage is good. Liriope spicata is considered hardier than Liriope muscari. It spreads by underground stems known as rhizomes and will fill in the area without much prompting. Liriope muscari is a clump-former and will take much longer to fill in the area.

Variegated liriope
Green-White variegated liriope (top)
'Big Blue' liriope (bottom)
Liriope 'Big Blue'

Barren Strawberry (Waldsteinia fragaroides) – Barren strawberry is a native, semi-evergreen ground cover that closely resembles edible strawberries. It grows four to six inches tall and spreads by rhizomes. Barren strawberry blooms in spring with yellow, star-shaped flowers. It tolerates full sun to part shade and a range of soils as long as drainage is good.

 

MORE

Growing lawns in shade

Groundcover photos

Efficient Garden Watering

 

 

 


home | terms of use | contact | search | site map
garden center
Copyright ©2017  DONNAN.COM  All rights reserved.