Monkey Grass Liriope Removal (Non-Selective Spray)

To control established liriope with a non-selective spray, first confirm the plant and check that the herbicide label permits use at your site. Glyphosate is one possible systemic option, but products and directions vary. Apply only at the labeled rate, protect nearby plants and water, and expect to assess regrowth before deciding whether a labeled follow-up is needed.

When liriope spreads beyond its bed, digging every clump may be impractical. Spraying can be an option, but a non-selective herbicide can also injure plants you want to keep. In site assessments, I start by confirming the plant, checking the product label and mapping nearby vegetation. Those steps matter more than choosing a stronger mix.

The directions below are for lawful, label-compliant use. A herbicide label is the authority for where and how that product may be applied. If the label does not allow the product on your site or for this use, do not use it there.

Confirm the liriope before spraying

Liriope is an ornamental, grass-like plant with narrow leaves that grow in clumps or spreading patches. Its flowers often rise on short spikes, followed by dark berries. The common name “monkey grass” can also refer to look-alike plants, so identify the target before using a non-selective herbicide.

Check several features rather than relying on a common name alone. Liriope commonly has wider, arching leaves than mondo grass, but leaf shape varies by species and cultivar. Flowers and berries can help with identification. If the plant is mixed with desirable groundcovers, or you are unsure what it is, ask a local extension office or qualified plant professional before spraying.

Mark the edge of the patch and note plants that must not be contacted. Pay special attention to nearby flowers, shrubs, lawn edges, tree seedlings and any water. Glyphosate can injure or kill desirable plants if spray reaches their foliage or green stems. A label-approved use does not make the herbicide selective.

Next step: Proceed only when you can distinguish the liriope from plants to keep and can direct spray onto the target.

Equipment setup and safety preparation

A hand-pump or backpack sprayer can work if the product label permits that equipment and application method. The goal is controlled coverage, not a heavy soak. Use the label’s required personal protective equipment (PPE), follow its mixing and cleanup directions, and do not use a sprayer that leaks or produces an uncontrolled mist.

Read the entire current label before opening the product. Confirm the active ingredient, permitted site, target, application method, PPE, weather limits, rainfast period and any required buffer zones. Glyphosate is a common systemic, non-selective herbicide, but formulations and approved uses differ. Never transfer a rate from one product to another.

There is no universal mixing rate for liriope. Measure and mix only the amount directed for your specific product and site. Use clean measuring tools dedicated to herbicide work, and keep the product in its original container. Do not add a surfactant or combine products unless the label allows it.

Before treatment:

• Check the sprayer for leaks and confirm that the nozzle works as intended.
• Calibrate it as the label directs so you apply only the labeled amount.
• Use a coarse, directed spray and keep the nozzle close to the target foliage.
• Shield nearby plants with a physical barrier if that can be done safely.
• Wear all label-required PPE, including any specified gloves, eye protection or clothing.

Check weather at the site, not just a general forecast. Follow the label’s wind, temperature and rain restrictions. Do not spray when wind may carry droplets off target, during a temperature inversion, or when rain is expected within the label’s restricted period. If you cannot apply without drift, postpone or choose another control method.

Next step: If the product label, equipment or conditions do not support controlled application, do not spray.

Field application and liriope control

Foliar application means placing herbicide on the plant’s leaves. A systemic herbicide can move within a treated plant, but it must first contact the foliage as the product label directs. Apply to actively growing liriope when the label permits, wetting the target leaves as specified without runoff.

Work slowly around the patch. Keep the nozzle pointed down and toward liriope, rather than spraying across the bed or through neighboring plants. Avoid applying so much solution that it drips from leaves or runs onto soil, paving or drains. A leaking nozzle, fine droplets or a gust can carry spray beyond the target.

If the liriope is growing through desirable groundcover, do not assume you can spray only the unwanted leaves. Shielding may help, but it cannot eliminate risk. Stop if the foliage is too tangled to treat without contacting plants you want to preserve.

Do not cut, mow or remove treated foliage on a schedule that conflicts with the label. The leaves may need to remain in place for the product to work as directed. Follow the label’s interval before judging control. If plants survive or regrow, re-treat only when the label permits and gives directions for another application.

Illustrative site examples: In a separated bed with no nearby desirable foliage, a directed spray may be manageable if the label allows that use. In a mixed border where liriope grows through perennials, the same product can damage the plants being kept. That second layout may call for careful physical removal instead.

These are examples of site conditions, not guarantees of control. Product directions, plant growth and site layout all affect the decision. Next step: Treat only the foliage you can reach and protect without violating the label or risking drift.

Sprayer cleanup and application follow-up

Cleanup limits accidental exposure and prevents herbicide from reaching plants or water later. Follow the product label for cleaning the sprayer, managing rinsate and disposing of leftover mixture. Rinsate is water or cleaning solution that has contacted the product inside the tank or equipment.

Do not pour leftover spray or rinsate into a storm drain, ditch, pond, stream or other waterway. Do not reuse herbicide equipment for watering or other household tasks. Keep people and pets away for the period and under the conditions stated on the label.

Record the product name, active ingredient, date, site and weather conditions. Note where you sprayed and any nearby plants that could have been exposed. Recheck the treated patch after the label’s stated interval. Yellowing or dieback may take time, so avoid judging results too soon.

If only some clumps survive, identify whether they were missed, shielded from spray or regrowing. Do not increase the mix strength to compensate. Check the label for whether another application is allowed, and follow its timing and rate. If the label does not authorize repeat treatment, do not repeat it.

Next step: Follow label directions for cleanup and wait the specified interval before deciding whether more control is needed.

Storage and seasonal care

Store herbicide in its original, clearly labeled container, secured as the label directs and away from children, pets, food and feed. Protect it from conditions the label warns against. Keep records of the product and application so you can identify what was used if questions arise later.

Do not save diluted spray unless the label says how to store it. Manage unused product and containers according to the label and local disposal rules. For future liriope control, check new growth before it spreads and decide whether spot treatment or physical removal is safer for the surrounding plants.

If the patch returns, distinguish regrowth from new plants before acting. A second application is not automatically appropriate. The label, the condition of the target and the risk to nearby vegetation should guide the next step.

Key point: Storage and follow-up are part of safe treatment. Keep the label available and use it for every later decision.

Frequently asked questions

These answers address common decisions about using a non-selective herbicide on liriope. The product label remains the final guide because rates, approved sites, timing and safety directions vary among products.

Can glyphosate kill monkey grass?
Glyphosate can injure or kill liriope it contacts, but results depend on the product, application and plant condition. Use it only if the label permits the target, site and method.

What is the correct glyphosate mix for liriope?
There is no single safe rate for all products. Follow the exact rate on the current label for your product and site. Do not copy a rate from another formulation.

Should I cut liriope before spraying?
Do not cut it on a schedule that conflicts with the label. Follow label directions about foliage condition and when treated plants may be cut or mowed.

How long until I know whether the spray worked?
Wait for the assessment interval stated on the label. Do not judge too early or apply more product before the label permits a follow-up.

Can I spray liriope in a lawn?
Only if the product label permits that site and use. A non-selective herbicide can injure turf it contacts.

Can I spray near flowers or shrubs?
Only if you can prevent contact with desirable plants and meet the label’s directions. If you cannot control drift or overspray, do not spray.

Can wind carry spray onto other plants?
Yes. Wind and fine droplets can move herbicide off target. Follow label weather limits, use a directed coarse spray and postpone treatment when conditions are unsuitable.

Can I use the same sprayer I use for fertilizer?
Use equipment only as the product label allows. Keep herbicide equipment clearly identified and do not use it for household or watering tasks.

What should I do with leftover spray?
Follow the label’s instructions for use, storage or disposal. Never pour it or rinsate into drains, ditches or waterways.

Is hand removal better than spraying?
It can be safer where liriope is tangled with desirable plants or near sensitive areas, though removal may require repeated work. Choose the method that controls the target while protecting plants you want to keep.

(This article was written by one of our staff writers, Arthur Langdon. Visit our Meet the Team page.)