We had a Memorial Day gathering yesterday and my gardening friends pointed out some plants that I thought were good plants with white, star-shaped flowers that have been increasing in numbers every year. They said they were bad weeds and we should remove them. What do you think?
— George Buchan, Evanston
The plant you describe sounds like a weed called Star of Bethlehem. I have an infestation of them in my garden and I’ve been fighting it for several years, causing a good amount of frustration. It’s an invasive, bulb-forming perennial that spreads aggressively in my lawn and garden beds. Star of Bethlehem starts growing in early spring with narrow, glossy, grass-like leaves that have a white midrib down the center. I find the white midrib hard to see on some plants. The grass-like foliage that grows 4 to 12 inches tall is the main identifying characteristic. The foliage does not have an odor like wild onions do. I noticed them starting to flower in my garden about a week before Memorial Day. The flowers are small and white, resembling a star. Most of the Star of Bethlehem in my garden are about 6 inches tall, and the flowers are attractive, so it makes sense that you didn’t identify them as a problem.
Star of Bethlehem reproduces through underground bulbs and bulblets. Each parent bulb produces several new bulblets annually, which form a dense colony over time. All parts of the plant are toxic if eaten. Our dogs have never shown any interest in eating this plant, so that has not been a big concern. The best control method for me has been carefully using a trowel or weeder to dig the plants out. When done properly by digging to about 4 inches deep, you will bring up a big cluster of bulbs with the foliage. It’s best to dispose of the bulbs in the trash or at a commercial landscape waste facility. Bulbs left lying on my patio for weeks still appear to be viable with foliage even remaining green for days. It’s an incredibly tough plant. I have tried using glyphosate, but that seems to just burn the foliage back with plants returning the next year. I may not have timed the applications properly, as the herbicide needs to be applied while the plant is actively growing, about three to four weeks before flowering. I think you should work on removing the Star of Bethlehem from your garden. There are many plants with great seasonal interest as potential replacements.
For more plant advice, contact the Plant Information Service at the Chicago Botanic Garden at plantinfo@chicagobotanic.org. Tim Johnson is senior director of horticulture at the Chicago Botanic Garden.
