Yellow woodsorrel (Oxalis stricta) grows very quickly during the summer, sprouting up in your fertile, moist, warm, manured soils – especially if there’s shade. Yellow woodsorrel reproduces by seed and is pale green in color with maroon leaves. They flower yellow, with five petals, and they can be very, very aggressive if your turf is weak, thin, or over-watered. Some gardeners use these bitter broadleaf weeds as salad greens or in drinks for summer-time, and old farmers sometimes chew on them.
What Yellow Woodsorrel Looks Like
Don’t confuse yellow woodsorrel with clover, especially when it’s in flower. Its leaves are heart-shaped, and it crawls across the ground as the plant builds up pressure. The pods shoot dry seeds several feet, and you can actually make the plants pop their seeds by touching them.
Preventing Yellow Woodsorrel With Regular Lawn Maintenance
The single best way to prevent yellow woodsorrel from growing is by maintaining your lawn, regularly pulling weeds before they’re allowed to seed. If you let them grow, they quickly choke out sunlight for your turf before they’re established.
Luckily, these types of broadleaf weeds are easily removed by hand. Once they’re removed, they generally don’t re-grow from their roots. As long as you effectively remove them from the area (making sure to throw them in the refuse pile) before they go to seed.
When Applying Chemicals to Yellow Woodsorrel
If you decide to apply weed control yourself or hire a lawn service to do it for you, pre-emergence herbicides should be used that prevent the seeds from germinating in the first place. Most of the post-emergent weed control products that you’ll find will provide lackluster results. Often, the best approach with chemicals is by spreading the herbicides in a single level, helping the herbicide stick with a sticker substance. This is because yellow woodsorrel has very waxy leaves and stems that resist water and cause it to roll off in beads. You can also spot-spray young plants when they start to grow after initial treatments.