Grass Clippings as Mulch

Hi All,
Would love some feed back from anyone who has ever used grass clippings as mulch. I have some large areas that I would like to try and suppress weeds etc with grass clippings as a cost saving measure. I have been told that grass clippings would work. This area is not near the house so old grass "aroma" is not an issue. The area I want to cover is under trees. What I would love to know from you gardening experts is, what will a layer of grass clippings do over the summer beside turning from green to yellow? By Oct or November (In MA) when I need to rake up leaves, will I be raking up all the old grass clippings as well or will it eventually mat down? I have of course layered grass clippings in my compost pile with leaves and other things and when watered down and layered pretty heavily, it appears to get pretty clumping and eventually moldy. Was just wondering if anyone out there has ever used grass clippings as a straight mulch? Kathy

Hi
I grew up in the San Fernando Valley in Southern California. My mother used to spread a thin layer of grass clippings in her very beautiful flower beds (1950s). She would scratch in clippings into the dirt. Every week and new layer. The clippings sort of composted into the dirt. Next week, mow the lawn, new layer. I do the same thing here in Phoenix AZ. I've had no problems with mold -- its HOT here and DRY. My roses do well with other amendments too. I use grass clippings in my compost pile also. Once I put a thick layer of grass clippings around my citrus. As the clippings decomposed they heated up ALOT. The buds on the citrus dropped before setting. I think maybe there was too much nitrogen. Could be wrong but a THICK layer was not good for the citrus.

Aguane - Thanks for getting back to me.... K

We use grass clippings in the vegetable garden (in the walkways and between plants). We mow a few acres, so we have ample clippings. Sometimes, we even use a home-made collector from the lawn tractor that chute-feeds into a towed wagon (how is that for lazy? lol)

Since the vege garden is in full sun, the grass matts down nicely. We spread about 12-inches and it matts down to an inch or so. Sometimes we need to replentish the layer, so we just add more clippings. Late in the year, we till it all under.

Here is a pic so that you can see the effect.

Hi Lynn,
Thanks for gettng back to me and with a visual! Your garden certainly looks healthy!...Kathy

Just don't put on a bunch of fresh at one time- it makes a chemically-unbalanced mush that is rank to boot! (and bad for anything growing there, as Aguane pointed out) It is not as good as suppresing weeds like other types of mulch, but any organic mulch is very beneficial. (if your grass has gone to seed when you mow, you can get grass seedlings, but his is rare). Good luck, I bet you'll do fine. K.

Yes, the application of grass as mulch is done at different times. Here's a few blurbs off the 'net that might help explain it better:

Grass clippings returned to the lawn provide up to 25 percent of your lawn's total fertilizer needs. Clippings contain about 4 percent nitrogen, 2 percent potassium and 1 percent phosphorus. While decomposing, they also serve indirectly as a food source for the bacteria in the soil, which are doing many beneficial things (such as decomposing thatch) for a healthy turf environment.
Source: http://extension.missouri.edu/explore/agguides/hort/g06958.htm

Grass clippings make a good mulch when applied in thin layers and allowed to dry between applications. Add additional layers each week as the lawn is mowed. With a few layers, weed seed germination will be checked. Grass clippings decompose rapidly, requiring additional layers during the growing season. A grass clipping mulch recycles its nutrients into the garden bed.

Do not apply fresh grass in thick layers as it will mat, produce foul odors, reduce air and water infiltration, and even become hydrophobic.

Do not use clippings from lawns that have been treated with herbicides, or other pesticides, for at least 4 weeks after application.

Grass clippings are a good choice in vegetable and annual flower beds that receive annual cultivation to prepare a seedbed. Around leafy vegetables (such as lettuce, spinach, chard) carefully place the mulch at the base of the plant.
Source: http://www.ext.colostate.edu/PUBS/GARDEN/07760.html

I'm following this thread with great interest. I need to mulch more and want to be economical.;-)

If you don't put fresh grass down, what to you do with it to dry it out?

Kristi

Put it down, actually!

Hi All,
Thanks for all your input and guidance! Think I will try a small area to start this year and see what happens this Oct/November with the leaves. Just don't want to have to rake up grass clippings AND leaves!... Kathy

Some folks use a mower to shred and shoot their leaves/grass into their adjacent beds. Others just mulch them into the lawn.

Starting with my first load of grass each year I place a thick layer of grass clippings on each bed. Then I add chopped leaves. I have used this method several years with my raised beds. I do not add anymore for the rest of the season. It keeps weeds to a minimum. The only time I add more is usually around the edges of the garden where weeds are more readily seen. I do this every year. I have abundance of grass and I save my leaves from the previous Fall. Linda

Hello all.
I've learned alot already just by reading this thread.
My neighbors lawn crew dumps all the grass clippings in the woodsy area behind our house. At first I was a little sour at the disregard for our property. Then I realized they were actually doing me a favor by providing free mulch! We let our clippings mulch back in the the grass as we cut so I never have any left over. I do use some in the compost bin, but I have not yet tried it in my new perennial garden. I'm learning that it has many benefits, but I don't find it aesthetically pleasing. Does anyone know if it is okay to mulch a thin layer, then cover that with shredded bark mulch?
Thank you! :)

Pat Lanza wrote the book on Lasagna Gardening. She did a clinic at our Flower Show in April. Every year she layers 1 part grass (green) to 3 parts brown (leaves, mulch) on her already existing beds. So, tmarie, I would say , "Yes". Linda

That is how I lay my compost over my existing beds. I rake back the mulch (bark) and then apply a liberal amount of compost 3 to 4" and then throw the bark back on top. Two days later my plants are singing Tosca.

Thank you!!! I can't wait to post some pics of the front yard progress. I'm missing my connecting cable for my cam, so I can't upload any yet, but tomorrow I'm off to get the missing piece!
All of you at DG have been my trusty sidekicks. I hope, as my knowledge and practice grow, I can help out as much as others have helped me. :)

I alwas run my grass clippings through my compost heap first. The reason I do not put the fresh clippings on my beds is due to the seeds.



Here's a great way to have the best compost that plants love !!!
http://paulgadawg.turnwill2.hop.clickbank.net

There are a number of grasses and grass mixes, of course. Not all grass clippings contain seeds....just need to know what you have that you're dealing with.

Clippings as mulch is one thing. Clippings into compost which is either used as a top-dressing or as a soil amendment is something else. I believe this post was about grass clippings that could be used as mulch. Soferdig, you and I are doing the same thing with compost. My perennial gardens are mulched with double shredded bark and it decomposes within 2 years, too. Every year, new bark mulch is placed on top and prior to that, I gently rake the old mulch to just loosen it up. It's work but it's fun-work. The reward lies under my feet where the rich, amended soil is filled with worms galore!!

One of the best ways to determine your soil composition is to actually get a testing kit to find your soil's chemistry. Doing a test will remove all guess work and give you results to work with.

All this information is very valuable. However I was just trying to get a read on imput using grass clippings as an inexpensive way to conrtol weeds in an area I may not even plant in so the composting aspect is really not an issue. I was looking for insights as to what will become of grass clippings just left in place, how long do they take to break down and need to be replaced...weeks? months? If I had done it in July, by November in MA when I have to rake alot of leaves in ths same area, will I also be raking up the grass cliipping or will they have matted down pretty much by then? There may not be an exact answer I realize due to weather conditions during the summer and fall etc. Wonder what would happen if I tried a thin layer now? Any thoughts anyone? Has anyone used grass clippings just for weed prevention not recessarily for potential composting too? Thanks everyone for sharing all your info. You all sound like pro's!...Kathy

And I'd appreciate a definition of "thin" and "thick" myself. Is three inches thin or thick?

Thanks!

Just don't make the layer too thick or it will shed water, also keep the fresh clippings away from growing plants, it will burn them. I try to stay at least an inch from touching. Occasionally I sprinkle a little nitrogen fertilizer over the top of dry clippings. Maybe once a year. When I want to plant something, I just pull the mulch back to lovely friable soil. Never waste good grass clippings. It's as good as compost, in fact it's ground composting.

I used grass clippings a few years ago -- about 4-5 inches thick -- as a mulch & weed preventer over a bed I had just planted with tomato seedlings. Worked like a charm. I just dumped them from the lawnmower bag and sort of spread them out from that. I had no weeds the whole summer. They heat up a lot, but tomatoes seedlings need warmer soil temps than most. I put them over bare space that may have had some baby weeds, but nothing tall.

Oddly enough, they did not turn to stanky mush. I would also say they tend to repel water when they dry and turn a nasty, unhealthy-looking straw color at the wrong time of the year, but by then they were covered with tomato foliage. It is a pleasure to dig into that bed now, but maybe all the tomatoes I never harvested had a hand in it, too. LOL!

I would never put nitrogen on top of grass clippings -- they already are a "green" (as opposed to a "brown") and no addtional nitrogen is necessary.

Suzy

Thanks Flowerlady and Suzy for sharing your experience!...Kathy