Weeds in artificial turf: bindweed from below, seeds from above, and what stops each

01Where are the weeds in my turf coming from?

Turf makers disagree about what comes from below. FieldTurf says “Weeds cannot grow through the turf’s durable backing” and that windblown seed sprouts in the infill, especially near the edges (FieldTurf Landscape). TigerTurf adds roots from nearby beds and lawns that “emerge through the turf backing” and a weak membrane underneath, and reads weeds in lines along the edges as creeping roots and weeds everywhere as a failed membrane (TigerTurf).

Either way, the backing has openings. Synthetic Grass Warehouse, a turf distributor, calls hole-punched backing the industry standard, perforated so water drains (SGW), and Firestone’s code requires the holes on a grid no wider than 4 by 6 inches (Firestone Development Code 16.6.4). A shoot that reaches one of those holes, an open seam or a lifted edge comes straight up; seams and edges have their own guides, visible seams in artificial turf and turf edges lifting.

Beside a Kentucky bluegrass lawn, the lawn itself is the intruder. CSU Extension describes it as sod-forming, spreading by underground stems, and Penn State Extension explains that those stems travel a short way below ground before surfacing as new shoots. How to close that gap is in artificial turf edging options. In Firestone, turf must stop at least 3 feet from the property line with living landscape in between, so there is always a planted border to keep an eye on.

02Why does bindweed keep coming back through turf?

Because its roots are out of reach. Field bindweed is on List C of Colorado’s noxious weed list, the species so widespread and well established that statewide eradication is impractical (Colorado Department of Agriculture). CDA describes it as a deep-rooted perennial that spreads from seed and from creeping horizontal roots, with seed that can stay viable in the soil for up to 40 years (CDA). CSU’s PlantTalk 2104 puts its roots at 20 feet or more.

CDA’s fact sheet calls it widespread in cultivated fields, pastures, lawns and gardens from 4,000 to 8,000 feet. If your lot was farm ground, pasture or a weedy lawn, assume roots survive below any dig for a turf base.

Turf works for you and against you. PlantTalk says shading bindweed out with cloth or other plants can control it, since it loves sun, and turf shades the soil it covers. But the vine creeps along the ground until it finds something to climb, such as a fence, and a stem that reaches a seam, a hole or an edge finds light. Check fence lines and seams first.

No single treatment clears established bindweed in one season, PlantTalk says. CDA’s advice is to keep stressing the plant until it uses up the food stored in its roots. On turf that means:

• Remove every shoot as it appears. Pulling won’t kill an established plant, but PlantTalk says persistence can reduce the energy in the roots.
• Paint or sponge herbicide on the leaves instead of spraying. PlantTalk suggests it where bindweed grows close to plants you want to keep; on turf it keeps the product off the rest of the surface.
• Never let it flower. PlantTalk’s first step is to stop it producing seed.

Treating it before the base goes in is covered in artificial turf over grass or dirt.

03What about goatheads and other seeds that land on top?

Seed is the other half of the problem. Puncturevine, the goathead, is on List C too. CDA describes it as a summer annual with tack-like seed capsules, whose seeds sprout after the first spring moisture and any wet spell after it and stay viable for 4 to 5 years (CDA). PlantTalk 2109 says it is most common in eastern Colorado below 6,500 feet; Greeley sits at about 4,670 feet and Fort Collins at about 5,000 (USGS). Weld County’s Weed Division lists lawns and gardens among the places it grows (Weld County).

A seed needs something to root in. Writing about fabric under mulch, CSU Extension says weeds “easily germinate on top of the fabric and root into or through it,” and turf behaves the same way. FieldTurf says clearing leaves and dirt stops a rooting layer from forming, and TigerTurf says a little debris, dust or infill is enough for a seed to germinate before its roots work down through the backing. So:

• Clear debris before it breaks down. Leaves, cottonwood fluff and pine needles are in leaves on artificial turf.
• Rinse and brush dust out of the infill. Which cleaners are safe to rinse off is in how to clean artificial turf.
• Pull seedlings while they’re small. FieldTurf says seed-grown weeds in turf usually come out by hand because their roots are shallow.
• Time a pre-emergent for goatheads. PlantTalk says certain pre-emergents applied around April 1 kill puncturevine seedlings as they germinate, but may be needed each April for several years because the seed lasts.

04Does a weed barrier or pre-emergent stop weeds for good?

No. Each one slows a different kind of weed.

A weed barrier is fabric that blocks light and roots from below. It does nothing about seed that lands on top, and it has joins and edges of its own. SYNLawn’s DIY guidelines say weed barrier and weed treatments “can lower your risk of issues” but “may not completely prevent weed growth,” and they place the fabric on top of the base in one step and on the subgrade in another (SYNLawn). Some neighborhoods require one: the Barefoot Lakes guidelines in Firestone say professional installation “must include a weed barrier” (St. Vrain Lakes Metropolitan Districts). The layers themselves are in what base goes under artificial turf.

A pre-emergent stops seeds from sprouting and does nothing to a plant that is already growing. Weld County’s weed sheet says of one that it “will not kill established growing plants.” So it helps against goatheads and other seed-grown weeds, not bindweed rising from old roots, and it has to be repeated each spring.

Ask before the job, and expect specific answers:

1. Is there a weed barrier, what kind, and does it go under the base or on top of it?
2. How are its joins overlapped, and does it run all the way to the edges?
3. Is anything sprayed before digging or before the turf goes down? Which product, and who applies it?
4. What happens if bindweed comes through in the first seasons?

More are in questions to ask a turf installer; afterward, read checking the base was installed. If weeds come up everywhere and the installer won’t return, see when a turf installer won’t come back.

05What can I spray on turf, and what about my trees?

Spot-treat one weed at a time. FieldTurf recommends a gentle, water-based weed killer for stubborn patches and warns off oil-based or harsh chemicals that could damage the fibers; TigerTurf advises against broadcast spraying the whole surface. Skip the salt: Synthetic Grass Warehouse says salt can clog the holes in the backing (SGW). Whatever you use, read the label. CSU’s GardenNotes #656 notes that using an herbicide in a way that doesn’t match its label is a crime.

Trees add a second risk. Under turf you can’t see where their roots run, and CSU says a tree’s roots can reach several times the width of its canopy. Root-absorbed and extended-control herbicides applied some distance from a tree can still damage or kill it. Two things to watch:

• Not every shoot is a weed. Aspens, cottonwoods and crabapples send up root suckers, and CSU lists spraying them as weeds among the common mistakes. A sapling coming up near a tree may be the tree.
• Read the label for trees. Some bindweed herbicides on CDA’s fact sheet say “DO NOT apply near or under trees/shrubs or where soils have rapid permeability.” A turf base is porous aggregate built to drain.

More on turf near trees is in artificial turf around trees.

06Who can spray weeds in my yard for pay?

Only someone with a Colorado commercial pesticide applicator license. The Colorado Department of Agriculture’s licensing program covers pesticides used against weeds, and says anyone in the business of applying pesticides for hire must be licensed with the Department (CDA). In April 2026 it reminded the public that applying for hire without that license can bring fines of up to $2,500 per violation (CDA). This is general information, not legal advice.

When a quote or a maintenance plan includes spraying, pre-emergent or bindweed treatment, ask whose license covers the application, then look the business up in CDA’s applicator search before you sign. Our artificial turf installation page covers the rest of a lawn replacement.