Replacing weeds with eco grass

Question: I need advise on how to go about replacing the weeds in my front lawn with something more ecological, like eco grass.  I have been collecting cardboard but am concerned the mulch will separate, expose the cardboard and create an eyesore.  Another suggestion is burlap covered with mulch which allows for planing in the future if desired.  The front yard gets a lot of sun.

Also what do you suggest for mulch?  pine fines, wood mulch or wood chips?  

Thank you for any suggestions.

responder: Answered by the Home and Garden Information Center (HGIC), University of Maryland Extension. For timely gardening information and tips, subscribe to our Maryland Grows blog and quarterly newsletter. Follow us on Facebook, Instagram, and YouTube. Replied April 30, 2024, 2:03 PM EDT
response: Hi,  Are you trying to replace the grass areas or are you wanting to cover up weeds in the established garden beds?  If it is for the grass area, you don't need to use the cardboard or burlap and can just use a thick layer of arborist wood chips which can be free or a small price. Shredded wood mulch will look more finished for the front lawn but that can be a personal preference. We actually don't advice using cardboard to smother since it can contain PFAS or forever chemicals or micro plastics. The burlap would probably allow the weeds to break through it rather quickly and it could also be coated in a material that isn't good for the soil. Typically the layer should be about 6-8 inches thick to deter any weeds from growing up through it. You can then plant into it by pushing aside a 'hole', adding some compost and planting plugs or a plant you wanted. In time the wood chips will break down and won't be so high. You can search for free arborist wood chips online and it should give you some options to sign up for some. It could be delivered on the same day or next day and it could be a large load. If it is more than you need you can always use what you need then offer it up for grabs in a local gardening group.  You could also put down woodchips to smother the turf/weeds, and then top dress is a more finished mulch for a more uniform look.  Let us know if you have further questions.  Emily

responder: The Question Asker Replied April 30, 2024, 3:22 PM EDT
response: Hi Emily     Thank you for the response. I am trying to rid the "lawn" area the is almost all weeds.  The garden areas have already been mulched with pine fines.  I am on Bartletts wait list for wood chips for a long time. Perhaps I will find another source. It would be a lot cheaper than hiring someone to do cardboard and mulch.     I am a little concerned about where to have them put the mulch. My front yard is surrounded by garden beds and any pile would smother them. I guess that leaves the end of the driveway.       Is it recommended to water wood chips once they are placed?  How often? How long does it take for wood chips 6' deep before it's ready for eco lawn seeds?      Joanna

responder: Answered by the Home and Garden Information Center (HGIC), University of Maryland Extension. For timely gardening information and tips, subscribe to our Maryland Grows blog and quarterly newsletter. Follow us on Facebook, Instagram, and YouTube. Replied May 01, 2024, 11:27 AM EDT
response: Hello Joanna,  A wood chip delivery truck will need easy access to dump the load in one spot, and the closer to the street, the more likely they will have an easy time unloading. For many properties, that is the end of the driveway. You might not get a notification it's coming, so plan ahead for getting your vehicle in/out, if needed.  You do not need to wet-down wood chips, but if they're dusty (not likely), you can. Wood chips should not be placed over an area to be seeded, though, unless you can wait long enough for the wood chips to self-compost into a fine "soil" for sowing on. Otherwise, you'd use the mulch to smother the weeds, then remove it to sow seeds on the weed-free soil surface. (Dead weed growth should ideally be removed before sowing or it will act like a mulch and interfere with some germination.)  Depending on what species are in the "eco lawn" seed mix you are referring to, cool-season grasses are often best sown in the autumn, not spring, so in that sense having the wood chips lay on the existing lawn/weeds for the summer and being more broken-down and therefore sow-ready by late summer or autumn may work out well without having to move them out of the way (or having to move much less material aside for sowing). We don't have a specific timeframe to reference for how quickly wood chips will degrade because it will depend on the species of tree that the chips were made from, the weather, and the microbial diversity in your soil below the spread chips.  Miri

responder: The Question Asker Replied May 01, 2024, 4:27 PM EDT
response: Miri,     Thank you for your response about wood chips.  I intend to sow eco grass in the fall so I will not be using wood chips to kill the weeds.       U of MD Extension does not recommend using cardboard under the mulch to kill weeds.You suggest putting a layer of mulch directly on top of the weeds. Would it behoove me to remove all the weeds before putting the mulch? (That has been suggested by a couple landscapers).  Do you recommend wood mulch or pine fine? How thick should the mulch be to kill the weeds?     Thank you.     Joanna

responder: Answered by the Home and Garden Information Center (HGIC), University of Maryland Extension. For timely gardening information and tips, subscribe to our Maryland Grows blog and quarterly newsletter. Follow us on Facebook, Instagram, and YouTube. Replied May 01, 2024, 4:34 PM EDT
response: It will help to remove what weeds you can before laying down mulch, but a thick wood chip layer can smother most weeds by itself, so it's not absolutely necessary. Hard-to-kill weeds like Bermudagrass and Canada Thistle, for example, may need spot-treatment with systemic herbicide to kill them, but you likely don't have either in this situation. Some researchers on Patuxent National Wildlife Refuge, who were putting some pollinator plant beds in among established turf areas, merely put down about 8 inches or so of wood chips and planted directly into that, not having cleared the weeds off the site first. They did have to deal with the occasional crabgrass or vigorous weed breaking through that layer, but by and large, it was successful.  Wood chip mulch can be laid more thickly than bark-type mulches (pine nuggets, shredded cedar, shredded hardwood, etc.), because it allows for better oxygen and moisture penetration to the soil below. (Even though you aren't intending to keep those weed roots alive, the beneficial soil microbes living in that soil are best not smothered, if you can avoid it.) The linked page by Washington State Extension goes into more detail about why wood chips are considered one of the best mulch choices by the author of that publication.  We do not have exact thickness measurements and weed species will vary in their susceptibility to smothering. Wood chips probably need to be at least 6-8 inches (when laid...they will degrade into a thinner layer, which is fine), based on anecdotal evidence. Bark mulches are usually laid only 2-3 inches thick.  Miri

responder: The Question Asker Replied May 01, 2024, 5:33 PM EDT
response: Miri,To be clear, I so not plan to plant in the wood chips.  My hope is to scatter eco grass seeds in the fall. Would that be possible if I put down   8” of wood chips? Thank you for the article.  Thank you.JoannaOn May 1, 2024, at 4:34 PM, Ask Extension <<personal data hidden>> wrote:

responder: Answered by the Home and Garden Information Center (HGIC), University of Maryland Extension. For timely gardening information and tips, subscribe to our Maryland Grows blog and quarterly newsletter. Follow us on Facebook, Instagram, and YouTube. Replied May 02, 2024, 12:19 PM EDT
response: Yes, we were attempting to clarify that seed-sowing is not compatible with using wood chip mulch (or any mulch), if the mulch remains in place (as opposed to being removed just prior to seeding) and has not completely decomposed into compost by the time seeds will be sown. Therefore, use a mulch to smother weeds and then move it aside when ready to plant (sow seed), or select an alternative weed-removal option (smothering with a tarp, digging them out, or herbicide) to prepare the ground for sowing. We can't accurately predict how long it will take 8 inches of wood chips to decompose fully, or degrade to a particular depth. You can try it, certainly, and just be prepared to remove whatever of the undecomposed mulch may remain by the time you're ready to sow the seeds.  Miri