by Andrea Laine, Master Gardener
I enjoy hand-pulling weeds. That’s a good thing because my flower beds were besieged by spotted spurge this summer.
Spotted spurge (Euphorbia maculata) is a prostrate, broadleaf summer annual that loves sunny, hot soil. It grows very quickly and forms a dense mat (or a shag carpet if you let it go long enough). It reproduces solely by seed and a single plant is capable of producing several thousand seeds.
The more I learn about spotted spurge the more I want to scream. And screaming is not a behavior I generally associate with gardening. The garden is usually my happy place, even when I am weeding.
As a master gardener, I know it is best to pull weeds before they go to seed. With spotted spurge that is within five weeks of germination. It is not uncommon for two or three generations to grow in just one season. Needless to say, it has been a challenge to capture this weed before it seeds.
Eventually, even I tired of weeding spotted spurge. So I hired a neighborhood teen to do the work for me. I demonstrated proper hand-pulling technique: Find the central stem and pull from the point on the stem that meets the soil, otherwise you may not get the whole tap root (which, by the way, can be two feet long for a spotted spurge). I watered the beds a couple days before he came because weeds are easier to pull from moist soil.
Later I learned that he had deeply raked the soil to loosen the weeds and make them easier to hand-pull. Of course, that had the unintended result of bringing more weed seeds to the surface. Sigh.
What could have caused this infestation in my yard? I am not certain, but I admit I did a couple things differently in the garden this year.
- For starters, I skimped on mulching. Rather than put down a few inches of hardwood mulch which goes a long way toward suppressing weeds, I chose a 50/50 mixture of pine bark fines and compost because I wanted to help replenish the soil. My garden is large and my resources (time, money and energy) are not! So, I consciously made a trade-off.
- Secondly, I asked the crew of nice men who mow my lawn every week to stop spraying glyphosate on the flower beds. I’m sure they thought they were doing me a favor, and maybe they were, but I never asked for this service and was bothered by what seemed like an indiscriminate action.
So, what’s a gardener to do?
My experience shows me that hand-pulling is no match for the perseverance of spotted spurge. I will try a different mechanical method, hoeing. A shallow hoeing three to four days after a rain dries out the soil surface and prevents weeds from becoming established. Technique is important here, too. Lightly scrape the soil surface with the hoe. The hoe cuts weeds just below the soil surface and brings few new weed seeds to the surface. The best hoes for weeding are the scuffle and onion hoe (also called tobacco hoe).
Time is also on my side, at least temporarily. Now that Fall is here, summer annual weeds like spotted spurge will soon be history. And I have all winter to ponder new strategies and, maybe, forget how much I hate spotted spurge.
If spotted spurge is a problem in your lawn:
For general weed management:
Spotted spurge is invasive in California, North Dakota, and New York state.