Scientific Name: Melilotus albus
White Sweetclover is a biennial native to Europe and Asia. It is not a native here in Wisconsin, and in fact is considered one of the 30 most invasive plants here. There are probably between 100 and 200 white Sweetclover plants in prairie #3, most at the edge between the prairie and the school lawn. The plants grow close to one another, but don’t seem to form the type of thick patches that can really crowd out the natives – at least not yet. Like other clovers, the white Sweetclover is a legume so it fixes nitrogen in the soil. For this reason, farmers will sometimes include it in their cover crop mix. It could very well be that the farmer who owned the land before it became a school planted it here in between corn crops. I did not see any Sweetclover in the other 2 prairie patches at the school
According to ediblewildfood.com, the entire plant is edible. Shoots and leaves of young plants can be prepared like asparagus and as salad greens, respectively. The best time to harvest them is as 1st year plants, before they’ve had a chance to flower. Once they’ve started flowering, they turn bitter. The flowers are edible and supposedly taste like vanilla. The plants are supposed to have a sweet/pleasant smell.
Here is my take on the edibility. The plants I tried were already flowering, so it was not surprising that the tiny bite of leaf out in the field was quite bitter and did not taste like vanilla. It was not bitter to the point of being totally unpleasant, though, and did smell faintly of vanilla and freshly mown grass. I would not seek it out for eating again as a salad green unless I can find it before it flowers.
I did pick a couple foot long sections of the plant to bring home and make tea. (Normally I would not pick flowers from a prairie patch that isn’t my own, but I make exceptions for invasives.) Dried, the plant had a very pleasant, sweet vanilla scent. I placed the dried leaves and stems in a teapot, poured water that was just below boiling temp over, and let steep for 5 minutes. When I opened the pot, the lovely vanilla scent was gone, replaced with something that smelled of fresh green beans. The tea was a little sweet and beany, not bitter at all. Again, not something I think I would seek out, but I also would accept a cup if offered. I might also try again with different water temperatures and steep times. I think a cold steeping might preserve the vanilla scent and flavor.
The stems of the plant do hold their sweet scent for a long time. I laid a few springs on my desk and days later when I sat down, their pleasant, sweet smell still wafted to my nose. While they aren’t the showiest flower around, they’d make a great addition to a mixed bouquet for their scent alone. And again, since they are an invasive here, I wouldn’t feel bad picking them.