Get Rid Of Wild Onion Before It Takes Over Your Lawn With These Helpful Tips

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Glancing upon your cherished lawn, you realize that an all-too-familiar, unwanted visitor again racks it: the wild onion, a.k.a. onion grass. These weeds embellished with waxy, grass-like blades pop up determinedly and give off an unmistakable pungent odor when mowed or crushed. The silent invaders create more than an aesthetic inconvenience and can turn your lawn into their stronghold in no time. How do you permanently get rid of onion grass, you wonder? Tug at those green shoots with the aid of a weeder (think of a physical tug-of-war), and you might achieve temporary relief. But, to truly root out this problem, a comprehensive approach consisting of a post-emergent wild onion killer and additional physical interventions becomes the ultimate game-changer.

Wild onions are resilient. Their subterranean bulblets lay dormant — a ticking time bomb of sorts — patiently waiting to sprout and claim your lawn. Killing onion grass requires a tactical understanding of their lifecycle — strike when they're but tender green shoots before they mature into the impervious enemy they are known as. However, the type of grass in your lawn will influence your timing for chemical attack. Spray your herbicide too early in spring, and you risk damaging warm-season grass; too late, and the invaders withstand your weed killer and continue to grow unabashed. Patience is of the essence here, as bringing about the downfall of this weed is never an overnight victory.

Physical control of onion grass

Manual removal is your first line of defense against a small-scale invasion of onion grass in your lawn — kick off by watering the infested area of your lawn to soften the soil. On the day of reckoning, arm yourself with one of the ultimate gardening tools — a garden trowel or, better still, a tool like the Fiskars Ergo Weeder, a small investment of $7.99 at Target that will pay off big. Slice through the earth to loosen it around the wild onion clumps. With a firm grasp near its base, gently pull out the entire clump. Remove the deceptively harmless bulblets, which could stage an insidious comeback.

Charging headlong into further physical control of wild onions, unleash repeated mowing attacks. This won't bring instant victory, but it's stealth warfare designed to slowly drain the life energy of the wild onions, leaving them feeble and barely clinging to their former glory. Keep up the onslaught, and over time, these once-flourishing foes will find your lawn far less welcoming. Go for the coup de grace by giving your lawn a fresh lease on life. With the onion grass defeated, seize this opportunity to rethink your strategies for keeping your lawn green and dense. That includes fertilization, along with reseeding and overseeding, which are proven weapons against thin and bare patches. Tailor your efforts to transform your lawn into an impregnable verdant sanctuary, leaving no space for onion grass to return.

Getting rid of wild onion using chemicals

When it comes to killing wild onions, pre-emergent herbicides fall short; however, post-emergent alternatives shine. Remember, you want to eradicate the sprouted foes without slaying your grass; thus, choosing the right weapon is crucial. Glyphosate, being non-selective, kills everything green in its path. Instead, consider selective herbicides such as dicamba, mecoprop, 2,4-D, and metsulfuron, which spare your grass while killing the wild onions. Even better, consider formulations with a blend of these ingredients, such as Southern Ag Lawn Weed Killer with Trimec, priced at $19.98 at DoMyOwn.

The first assault is best launched in late fall, catching the onion grass off guard just when it peeks above the soil. Yet, due to its resilience, a follow-up herbicide application in spring is crucial to ensure its complete downfall. But beware, for the onion grass has a trick up its sleeve — its sleek, glossy leaves that excel at repelling chemicals. A cleverly added surfactant, like dish soap, ensures your herbicidal concoction adheres, penetrates, and decimates.

Tread carefully around ornamental plants and newly seeded lawn spots, for herbicides could harm these sensitive zones. Remember, suiting up in protective gear is a non-negotiable. In the age of environmental stewardship, horticultural vinegar emerges as an eco-friendly wild onion killer. However, be wary, for vinegar is indiscriminate, and applying it is an unintentional way to kill your grass.