Story and photos provided by Laura Payne, Volunteer Coordinator for the Botanic Garden at OSU
Spring is always the best time to come out to The Botanic Garden at OSU and visit the rock garden. The myrtle euphorbia, creeping phlox, and a variety of bulbs are blooming profusely right now displaying colors of bright green, blue, pink, purple and white.
The Myrtle Euphorbia, Euphorbia myrsinites, or Donkey Spurge, is one of my favorite plants in the rock garden. It is heat and drought tolerant, has very unique flowers and when it seeds, the seed pods burst and you can actually hear them popping. It sounds like stepping on bubble wrap. Those little seeds get dispersed through the air and can travel a pretty good distance. Now the bad news about this plant; it is a spurge, so it has a milky latex sap that can cause skin irritations, and because it reseeds so readily, this plant can become invasive. My advice would be to cut the seed pods off before they burst and enjoy this plant for the brilliant color and unique foliage it provides. Myrtle Euphorbia is best grown in dry, well-drained soils in full sun. It is quite tolerant of poor soils, including rocky, sandy ones.
Creeping Phlox, Phlox subulata, is a very large genus of perennial flowers. These flowers fall into the Polemoniceae family which contains around 12 genera of plants that are native to America. The genus Phlox was classified by the father of botany, Carolus Linnaeus, in the 18th century and he named it from the Greek word for flame. This genus contains about 50 different species of both annual and perennial flowers that come in a solid color, bi-color, striped or with a dark center. If you cut the phlox back about half after it has flowered, it will thicken up the foliage and create a nice carpet ground cover. I have heard of gardeners using their weed-eater to cut back the phlox and this would make the work a lot easier and faster. Phlox subulata grows best in sandy soils in the thin forested ridges from New York west to Michigan and throughout the Appalachians, however most any gardener can grow this plant in their own garden.
Because of plants such as the phlox, forsythia, spireas, and lilacs, in the spring I can travel down a dirt road and know where houses used to stand. These are the types of plants that were passed down from generation to generation and we are happy to display them here at The Botanic Garden at OSU.