Hard to Kill Lawn Weeds

Wild Violet – What Weed Killer Can I Use?

Wild Violets Viola papilionacea

Wild Violets

QUESTION: My yard is overrun with violets my neighbor planted them a few years back. They grow faster than weeds. What can I use to rid of them that wouldn’t kill my grass?

ANSWER: Wild violets are winter annual or perennial weeds that often grow in clumps. The plants are spread by rhizomes and are capable of living for more than two years. They are often found in shady locations.

Proper Lawn maintenance is the key to control of wild violets (and most lawn weeds). First, select adapted turfgrass cultivars for your area and then properly fertilize, mow, and water to encourage dense growth.

Wild violets are difficult to control. It will require a series of post-emergent herbicide applications – use a broadleaf weed killer labeled for use on lawns. Repeat applications of two, three and four-way broadleaf herbicides are usually required for extended control.

For Selective control – it won’t kill your grass – look for a product that contains triclopyr. A product that I’ve had some luck with is Speedzone, which does not contain triclopyr but will work.


Eradicating Wild Onions


How do I get rid of wild onions on my lawn??


Wild onions (onion grass) are hard to eradicate because they are perennial weeds that sprout every year from bulbs and the thin leaves have a waxy layer that repels herbicides.

The most eco-friendly way to “try” to get rid of them is to dig them. Use a 4-inch blade or thin hand trowel to cut a 3-inch circle around the wild onion plants – remove the core and fill with a divot mix – topsoil + seed.

Pulling does not work because the bulbs will be left in the ground to re-sprout.

If you have a serious problem, use a post-emergence herbicide with a surfactant. The surfactant – or spreader/sticker – will help the chemicals penetrate the waxy layer. Three-way broadleaf herbicides containing 2,4-D, dicamba and mecoprop (MCPP) will control wild onion with repeat applications.

Common 3-way herbicides you can find at retail stores that are labeled for wild onion and wild garlic include:

  1. Bonide Weed Beater ULTRA
  3. Spectracide® Weed Stop® for Lawns
  4. Gordon’s SpeedZone®

To eradicate wild onion, you will need to treat it twice a year and for more than one year. Treat in early spring and again in the fall.

Tip: Mow wild onions before you apply the herbicide and then wait at least two weeks to mow again after treating.


Vine Weed in My Lawn


There are vines growing in my grass killing it. What can I use?


Hi Claire, the first step in weed control is identifying the weed. Do you have pictures of the problem vine that you can share with us?

My best guess is it is either a vine-type weed such as Ground Ivy/Creeping Charlie, Common Mallow or Field Bindweed – You can use my custom lawn care search to find bindweed information.

Vines and “vine-type” weeds are always hard to kill in lawns. You will more than likely have to spray them twice – once in the spring and again in the fall. Use a broadleaf lawn herbicide that contains triclopyr as the active ingredient – Ortho® Weed-B-Gon® Chickweed, Clover and Oxalis Killer is one brand that you can buy at local hardware or home stores. Combination products that contain 2,4-D, dicamba and MCPP/MCPA – will also work but are not as effective as triclopyr products. Gordon’s Speedzone is a good example of a combination product. I have had good results with Speedzone on hard-to-kill weeds.

Lawn service directory

If you can identify the vine – or send us some pictures so we can help ID it – we can give you a better plan of attack.

Perhaps you’d like to see these pages . . .

  1. How to Sharpen Mower Blades
  2. Calibrating a Drop Spreader
  3. How to Compost Grass Clippings

Thistle – When is the best time to get rid of thistle?


What is the best way and time to get rid of the thistle in my my lawn and vegetable garden?


The best times to control thistles – as well as other broadleaf weeds – are in the fall (September through mid-October) or spring (late April through mid-June). Herbicides must be applied when weeds are actively growing and air temperatures are roughly 60º to 85º F.

Control perennial thistles as soon as they appear and before they have a chance to spread by underground roots.

See Canada Thistle

Broadleaf herbicides containing 2,4-D and MCPP can control thistles in lawns. I’ve had good luck with Gordon’s Speedzone. Always use a spreader/sticker to help the weed killer penetrate the waxy leaf layer.

In gardens, it is best to spot-treat thistles with a non-selective herbicide containing glyphosate, such as Round-up. There are several brands of generic Roundup that cost a lot less and are just as effective. Look for something that is 41% Glyphosate.

See this article for more info on generic glyphosate

Find out how much your job will cost