Mimosa: Just a little on the trashy side

Mimosas are putting on their summer show of silky, pink flowers all over southeastern North Carolina. With beautiful flowers and incredibly fast growth, you would think this medium-sized tree would be a popular addition to the landscape. Unfortunately, this plant tends to be a little on the trashy side with seedlings popping up all over the place.

Further limiting its use is a vascular wilt disease commonly called mimosa wilt that eventually kills the trees, but if you can enjoy a plant while it’s around and not get too attached, mimosas can add color and interest to the landscape.

A relatively new addition to the mimosa line-up is one called Summer Chocolate. Discovered in Japan in 1990, it’s one of those plants that becomes a must-have when you see it. While the flowers and the basic shape are pretty much like any other mimosa, the leaves are a rich, burgundy color. Unlike most plants we grow with burgundy foliage (Japanese maples, Forest Pansy redbud), the color intensifies as the heat builds, but mimosa wilt may eventually kill Summer Chocolate, just like other mimosas.

Back in the late 1940s, two selections of mimosa were made that claimed to have resistance to this wilt disease caused by a fusarium fungus. Even with the regal-sounding names of Charlotte and Tryon, they succumbed to the wilt pretty quickly. You may still see these listed as resistant clones in catalogs, but they will die along with the seedlings that come up on the ditch bank.

Speaking of ditch banks, as a pudgy, little kid growing up in Warren County, one of my favorite trees to climb was a mimosa. It lived out near the road and had just the right branch structure for a short-legged rug rat to climb all over its canopy. The fusarium wilt claimed it about the time I lost interest in climbing trees.

Dr. Tom Ranney, a plant breeder who works with N.C. State University at the Fletcher station in the mountains, has been working to create wilt-resistant clones that are also sterile. Plant breeding and selection takes a long time, but a mimosa that doesn’t die from the fusarium wilt and doesn’t produce viable seeds will be a big hit. Let’s hope Dr. Ranney is able to release a selection sometime soon.

As you might expect from a somewhat trashy tree, mimosa can handle just about any growing condition, as long as it’s not too wet. It will tolerate dry soils, high pH, low pH, lots of wind and just about anything else. This 20 to 30-foot tree will even grow pretty well where the soil has a bit of extra salinity. You will need a site with plenty of sun if you expect