Banishing the Uninvited


My garden on the mulch

I know that mulches are not traditionally used in vegetable gardens, but flossing, driving cars with decent gas mileage, and using Wikipedia to settle dinner-table debates are not traditional, either, and we find that stuff reasonable at this stage of human development.

When considering whether to mulch your vegetable garden, the great question to ask yourself is, do you want to be Sisyphus, or not? 

Because you are inevitably serving up to nature a nice cozy rectangle of carbon and nitrogen that will get filled.  And I don't care if you start with sterilized soil in a raised bed.  Eventually, you will get weeds.  And unless you are there to pluck them out every night, they will become overpowering.

Loosestrife 021

My garden off the mulch

Here are a few interesting facts about weeds that I just learned from University of Cambridge botanist David Briggs:

  1. Weeds adapt quickly to all kinds of pressures, including the pressure of finding themselves in an immaculate botanical garden, staffed by many young gardeners with horticulture degrees. In such a situation, some of them flower earlier than they do in nature or in the gardens of the sloppy, hoping to set seed before anybody notices.
  2. Many small-seeded weed species can be lulled into dormancy by even a shallow covering.  In other words, they need light to germinate.
  3. However, many weeds of crop lands produce a lot of seed that is viable for a long time, leaving "seed banks" that persist in the soil…just waiting for some foolish gardener to bring out the rototiller and expose them to the sun.
  4. Seeds of some weeds can persist in the soil a hundred years.
  5. One experiment looked at a wheat field and found in 34,000 seeds in a single square meter.

So, as Susan Harris suggests, rake those fall leaves onto your vegetable beds.  Or order a truckload of wood chips, or bury the place in spoiled hay.  And don't clear it up in spring.  All your crop seeds require to germinate is a shallow stripe of exposed soil made with the handle end of a shovel. 

Safety first!


  1. This is a good question that I have been asking myself and if anybody has a good answer I would like to hear it.

    Come this spring I will be planting my first in the ground veggie garden (not in pots) do I mulch or not?

    I feel a little stupid asking what do I do with the mulch at the end of the growing season?

    I realize I will need some thing to suppress the weeds will the mulch need to be removed? Or can I just till it back into the ground for next year I know I may sound a little on the lazy side but I just don’t want to create more work with the limited time I have right now.

  2. Wood chips in the vegetable garden is the number one search that brings people to Outside Clyde. I’ve inter linked several posts and send them off to Linda Chalker-Scott. The word is getting out that mulching your vegetable garden saves major weeding time and improves the soil dramatically. I swear by arborists wood chips. They are the best as far as I am concerned.

  3. Zone 9, I’m with Christopher C (and the Troll). Don’t remove it–it will break down on its own. Mulch is the only fertilizer I add to my garden, and my garden generates a ton of gorgeous food.

    Just reapply every year, and make the earthworms happy.

  4. Definitely mulch in the vegetable garden
    1)Helps with weeds
    2)Helps with moisture (hello, lack of rain here in the northeast this past summer)
    3)Breaks down into useable organic matter
    4)Makes your veg. garden look prettier

  5. I’m convinced that some weeds mimic nearby garden plants. I swear I see the same species sporting two distinct leaf shapes or colors depending on what other plants they are living near. Its as if they were smarter than the gardener…

    I’m a mulcher. I have no boundaries about where it belongs or shouldn’t be used – I put it everywhere.

    Improving your soil is a constant endeavor. The more effort you put into it the more you’ll get out of it.

  6. Anyone have experience mulching large veggie gardens with straw? My church has a half acre garden where we grow food for the homeless. The garden team is pro-till, so we till every year (have already tilled this fall)and this year are mulching the whole enchilada with straw. Any advice on how deep we must mulch to get weed supressing benefits, or whether wood chips are better by far?

    And another question: the strawberry beds have been neglected, and are full of weeds. They’ve produced well for the past two years despite that. What do we do now? Best to completely redo the beds, or is it possible to save a totally weed infested strawberry bed (about 300 sq ft)? If we are able to clean the beds up, what to mulch with?

    The church garden is more small-scale farming, and I’m used to my fifth-acre home garden! So advice welcome.

  7. The straw made a huge mess of my veg garden at my old house. Lots of weed seeds came with it, I wished that I had used wood chips. Unless your full time job is weeding your garden, you really must mulch. Nature will fill any void.

  8. 1) Hmmm, “young” gardeners?

    2) Ruth Stout was preaching (back in the early 1950s) the message to MULCH MULCH MULCH your vegetable garden. Her book was my mother’s bible (n.b., it would be wonderful if that book was back in print)

  9. I have one issue with mulch. Last year I mulched my garden with leaf mold and compost, but found that all the unwelcomed critters like to hide in it. I had tons of pill bugs eating my new seedlings, and they hid in the mulch. I had an infestation of stink bugs, which also hid in the mulch. I’m also concerned that leaving mulch on the ground overwinter just gives the pests a place to hang around so they can bust out again in spring. What do you do about this problem?

  10. I’ve had trouble with straw and hay sprouting, too. Ruth Stout recommended using spoiled hay–with most of the seeds, in other words, ruined by moisture–and said that if you have weeds in your garden despite a grass-based mulch, the mulch is just not deep enough!

    But I think leaves and wood chips make much more sense.

    Lisa C., strawberry plants are only really productive in their second and third years. You might want to see what kind of a harvest you get in your current bed–but at the same time, establish a new one with some of the baby plants it is producing.

  11. Here in So Cal in my veg garden, I mulch with layers of newspaper covered with composted horse manure or my own compost. This covering helps maintain soil moisture, encourages earthworms & as it breaks down, improves both tilth & fertility. Whenever I replant a crop, I re-paper & mulch.

  12. The only one down here this neck of the woods with five continents 105 countries on his belt declares:

    All this is a bunch of CRAP, or manure if into the organic fad, I have got no weeds to worry about, with over one hundred botanically idenfied species in my humble, intercontinental tropical garden….

  13. Fresh wood chip mulch breaks down quickly in my area and makes absolutely the best composty soil. But, I have found the weeds love it too so I have to mulch the mulch. Strangely, plain old coastal burmuda hay works well for me. I have not found it to sprout and it seems to keep other weeds well under control. I use about 4″ and refresh it twice a year.

    About the tilling, doesn’t it break up the beneficial mycorrhizae?

  14. Lisa C. – I like straw as a mulch. It does blow away until it gets soaking wet with snow or rain and it works best if it is really deep (one foot of dry will slump down to 4 inches by spring). Earthworms really like the cellulose in dry straw or shredded newspaper. Any wheat that sprouts is easy to pull (I simply yank it out and lay it down to compost right there in the garden).

    A lot of farmers use special plastic sheeting on top of tilled soil and I have had great success with black plastic sheeting as a mulch with holes cut for each plant. I leave it exposed during the winter to warm up the soil and then cover it mid-spring to keep it from over heating. By fall the mulch has broken down and can be moved under the plastic. It is a pain to pull up all the plastic and work the composted straw into the bed but the time saved by not weeding all summer is worth it.

    Strawberries go downhill with weeds, they don’t like competition. I would hand pull and hoe out all that you can and then lay down fresh mulch. You can mound it up kinda high around the plants, it protects them from winter wind and they will creep up and over the mulch by springtime. Keep in mind that strawberries are not a forever plant, they eventually catch a number of diseases (they are in the rose family after all) so you have to replace them every once in a while and its best to remove all of them and start over. Even better to not grow the new ones in the same spot.

    One trick to keep weeds from sprouting in your mulch so much is to keep the wood chips to a layer around an inch thick or less. That way the mulch stays drier and the seeds don’t sprout as much. This works best if you have a barrier between the mulch and the soil, could be newspaper or plastic sheeting or landscape fabric. Just remember that you will have to remove the layers and pull it all up at some time.

  15. I have such a problem with weeds at the community garden – and they suck all the nutrition from the soil. I planted fall rye this year to build the soil and hope that a year of constant weeding will start to break the cycle.

  16. I just spent over 30 hours attending a certification class on compost and mulch. Who knew it was this in depth and interesting !
    Briefly, the name of the game is matching the type of mulch with the type of plant that you are growing.
    As an example ; vegetables are a fast growing one season crop so you want to use a mulch that has already started its decomposition.
    Mulches require nitrogen to break down. If your mulch is too newly harvested it will use/take/steal/ borrow / exchange the nitrogen that is in your soil ( different rates apply ) . This would be fine if you were planting a woody shrub or tree that can wait the time for the nitrogen to become available via decomposition, but for a fast growing seasonal crop such as veggies the desired effect is threefold : to feed the soil, conserve evapotranspiration and suppress weeds.
    A fresh load of green mulch ( non partially decomposed) will suppress the weeds but won’t benefit the plant with nutrient value until it is working in harmony with the natural food web.

  17. It’s been so long since I haven’t mulched my garden that your comment of “mulches are not traditionally used in vegetable gardens” startled me. After so many seasons it’s easy to think that using mulch to prevent weeds and break down into better soil is an obvious addition to the garden. Thanks for reminding me not to take my mulching efforts for granted.

  18. Mulching in a vegetable garden is great, but it makes slug control awfully hard, as you’re giving them an incredible habitat with those layers of moist, rotting organic material. I’ve found mulch works best with crops slugs tend to ignore, like tomatoes, beans and corn, but it can be tough to grow cucurbits and greens in mulch in the northeast if you live in a slug-prone area. That’s not only a gardener’s opinion, but the opinion of many local farmers I’ve talked with.

  19. Eliza makes a good point regarding the proliferation of slugs under your mulch layer. We live in slug utopia in the Pacific Northwest and I still mulch with rotting leaves, newspaper, compost and the like anyway. Because it is so beneficial to the tilth and health of the soil. Slugs are part of the soil ecosystem too, albeit a curse to many as are weeds. But, due diligence with the sharp end of your shears whenever you spot one will keep their numbers at bay. g’won take a stab.

  20. I use pine needles for mulch in my vegetable gardens for several reasons. 1) It’s free in this neighborhood. (I rake it from the streets when my own supply grows short.) 2) It’s easy to rake away after the crop is harvested to get ready for the next crop–you can’t do that with arborists’ chipped wood, which I use on paths between the beds. 3) It doesn’t decompose much through the growing season, so it doesn’t rob nitrogen from the crops and it doesn’t need to be replaced in mid-season. And here in north Florida, some crops have really long seasons–peppers go from March through December. 4) Only the most persistent weeds with underground runners grow through it. New seeds don’t sprout atop the pine needles.

  21. Ginny, I am so glad to see someone else rakes pine needles from the street. I use to take my little red wagon down to the cemetary and rake up the white pine needles from the paths. The children would help until they realized “normal” people don’t do this. On my vegetable garden I spread newspaper and top with grass clippings during growing season. When the veggies are all yanked I pile mowed leaves.

  22. I started the mulch on my vegetable gardens this last year and was amazed what a difference it makes. I didn’t know seeds could persist that long, but I suppose it makes sense. Amazing.

  23. I garden in SE Michigan and I mulch heavily with straw. I have found that some bales seem to sprout more than others but it is still totally worth it to mulch with it. This fall I am making paths around the edges of my (new last spring) vegetable garden with landscape fabric and wood chips (made of shredded pallets from the city of Ann Arbor) to hold down the weeds that love to grow around the edges.

  24. I started mulching the veggie garden a few years ago. I was sick of weeding and watering and saw that elsewhere in the yard, where mulch had broken down, we had the most lovely miles of worm casings. My Master Gardener manuals both say not to mulch because it robs nitrogen. However, in my limited experience, by the end of the season the benefits of having reduced the weed competition far outweigh that little bit of lost nitrogen. (And if I really need nitrogen, I can always grab some extra compost.)

  25. Lots of great comments here. Whoda thunk we could get so excited about mulch?
    My dad used to have me add the lawn clippings as mulch but as I learned more about horticulture and gardening I changed my thinking. Now last years composted yard debris is my favorite. Just be sure not to add last years tomato plants to the compost. It can cause problems with next years crop. I must admit that I do use the lawn clippings in the valleys between rows for a nice foot path.
    I’m all for making vegetable gardens easy and not to much of a chore but there is something relaxing about walking the rows with my hula hoe in the evening after working all day.

  26. Spring 2010 I used layers of newspaper topped with wheat straw, putting it down late Feb when the snow peas starts went into the ground.

    By summer it was 90% broken down and I could plant the next seedlings with my hands if I had wanted to – no digging required.

    Between rows I use strips of old carpeting with several layers of newspaper underneath.

    In zone 7 NE Oklahoma, slugs rarely survive our awful summers but little frogs live in the mulch.

  27. I mulch veggie garden paths with cardboard (lots of cardboard) covered with wood chips, renewed every year. Sometimes I renew the cardboard, too. I finally got my hands on some old hay bales that I have patiently been spoiling and I am hoping to plant right in them as per Ruth Stout’s method, currently in efficient use at Laughing Dog Farm near me. All these mulches are great at building soil. Great post and comments!

  28. Does anyone have a solution to the slug problem? We have more slugs than you can count in our veggie garden. I do think the mulch is to blame.

    We go out at night with flashlights and buckets of soapy water to catch them, but even so they can get the better of our plants.

    We can put out beer or a commercial slug-killer, but is there something better?

  29. “mulches are not traditionally used in vegetable gardens” – This was news to me! Mulch straw from the local garden center looks great & just gets decomposed into the soil at the end of the season. Easy peasy.

  30. Someone else has already mentioned Ruth Stout, who must be the patron saint of permanent mulching. Her many books — all pretty much the same info but with different titles 🙂 — were part of my earliest self-education as a new organic gardener in the early 1970’s. She used ‘spoiled hay’ and anything by her is worth scouting for — you can still find her books in used bookstores.

    After her timely demise (I think she was in her 90’s) her regular articles in OG magazine and books began to disappear. But a few years ago I discovered a marvelous short film that was made about her. She had quite an interesting background — raised as a Quaker, did some saloon-busting with one of the big Temperance ladies — and was chastised by her husband for occasionally gardening in the nude. The video is still available, from Bountiful Gardens for one. Her brother, Rex, was a noted and prolific writer of mysteries. And also one of the country’s early experts on orchids. Interesting family!

    I do think what mulch we choose should be based on climate, crop and of course, availability. My gardening experience is all in the arid West, so although we do have some slugs, pillbugs, etc, pretty much any mulch is good mulch. Straw or hay beats down pretty quickly in the wet.

    One technique that I find very helpful, particularly for reducing water use but also for reducing weeds, is to plant most vegetables in wide beds rather than rows. I use a version of the Chinese raised bed system. The 3-4 ft wide beds create a continuous canopy of leaves that shades the ground, conserving moisture and reducing weed germination.

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