Would like list of ground cover plants that would grow under oak tree in 8b. If there is Allelopathy do any ground covers or low height plants survive?

Answer #1 · Maple Tree's Answer · Hi Andrea-I live in Southern California where most of us cherish our oak trees. As far as I know and have seen the oak tree does not produce chemical compounds that are toxic to other plants. Several problems with planting under the oaks have to do with finding plants that will grow with very little sunlight and have to compete with the trees need for water and nutrients. Many plants have a hard time growing within an area of soil that is hard due to the dense root system of the oak. Keeping the health of our oak trees is our number one priority. In my location most cities have restrictions on removing and pruning in order to keep our trees healthy and or not being removed. Any changes in the soil or disturbance of the roots can cause the death of these trees. Many plants that need occasional fertilization and or additional water, especially during the warmer months, to stay healthy can impact the health of the oaks. In my location there are many beautiful landscapes with plants and groundcovers among these beautiful trees. Most of these plants including ground covers are native plants and or others that survive with the same nutrient and moisture requirements of the oaks. Which of these plants will do well will be determined by your hardiness zone, 8b, and the amount of sun and moisture they will be getting. If there is enough soil above the roots of the oak there are several groundcovers that would do well. As long as any tilling of the soil that may harm the roots is not done or any additional soil doesn't have to be added above the existing roots the oak can be planted under. You may want to check with your local Cooperative Extension Service and quality nurseries, not the box stores, for information as to what plants will grow under the oak trees in your location. They may have a list of plants that will do well in your hardiness zone specifically under the oaks with the same water and nutrient requirements of the oak. I noted a few links below to articles by the extension services in my location that may be of help to you. The articles explains things that need attention when planting under an oak tree and list some plants you can use that may work well in you location. Some of the plants listed are groundcovers and some are plants that can be used to fill the area in with lower heights. You can google these plant names to see what hardiness zones they will grow in and find pictures of these plants. Just click on the links below to go directly to the articles and plant files. One groundcover I see a lot of in my location under many trees including the oaks is the Vinca Minor and Vinca Major (periwinkle). This groundcover does well once established in full shade or filtered light and requires very little water. Asian Jasmine has also done well under the oaks and again needs very little water once established. Both these groundcovers I believe would do well in your location.

http://sonomamg.ucanr.edu/Sonoma_Gardener_Articles/Planting_Around_Oak_Trees/

http://ucanr.edu/sites/scmg/files/29793.pdf

http://www.gardenality.com/Plants/301/Groundcover-Plants/Vinca-Major.html

http://www.gardenality.com/Plants/300/Groundcover-Plants/Bowles-Vinca-Minor.html

http://www.gardenality.com/Plants/282/Groundcover-Plants/Asian-Jasmine.html

Please ask if you have any other questions.

John)