From the Garden

The Many Benefits of Mulch

By Megan Cain | Photos By Megan Cain 8

In the last blog post, I wrote about how mulching your garden allows for easy spring maintenance. If you’ve worked or gardened with me in the past you might think I am a little mulch crazy…and you are probably right. It pains me to have bare soil in my garden, although it is a bit of a necessity sometimes. When considering whether to mulch or not, think about nature. Bare soil is not a common occurrence in the natural world. Bare soil is susceptible to erosion and compaction from wind and water. It is also an invitation for weed seeds, whose job is to be the first line of protection for the soil. They get in there and stabilize the soil with their roots and provide some shade from the beating summer sun until the next generation of species starts to colonize the area. When you cover the soil of your garden beds with mulch, you are protecting it from a weed seed party.  The first benefit mulch offers is to keep down the weeds, which makes every gardener happy. 

The freshly mulched spring garden.

If you live in the Madison area, you remember the drought of last summer when gardens everywhere were suffering. If you garden was heavily mulched like mine, you didn’t have to water much more than usual and your plants didn’t suffer as much as in other gardens. This is because mulch keeps the soil insulated and traps moisture, which allows you to water less than if you had bare soil.

Most gardeners know that soil health is one of the main building blocks of a successful garden.  The mulch in your garden breaks down over time and adds organic matter to your garden.  Each year I use about 15 bales of hay on my garden and I am amazed that they just seem to disappear by the next year.

Mulching can also help keep down the spread of disease in your garden. If you mulch nothing else, at least mulch your tomatoes. We have a lot of soil borne tomato diseases in this area that can splash up onto the plant when it rains if your soil is bare. Mulching around your tomatoes covers the soil and can slow down the spread of disease.  My tomatoes are mulched heavily and are still pretty disease ridden by the end of the season, but I think the mulch helps the plants stay one step ahead of the disease so it doesn’t interfere with their production and my harvest.

The mid-summer garden - weed-free and neatly mulched.

Mulching garden beds with marsh hay is my first choice, with straw as my second. You can mulch with leaves, although if they aren’t shredded they have the tendency to mat together into a big impermeable sheet.  Grass clippings and newspaper are fine as well. I would let the clippings turn brown before I put them on my garden and the newspaper needs to be weighted down with something so it doesn’t blow away. Woodchips are not for vegetable garden beds (keep them in your perennial beds) because they tie up nitrogen as they break down. I do use woodchips in my aisles because they last the full season without needing to be reapplied. I also like the aesthetic effect of having two different colors and textures in my garden beds and paths. Sometimes I’ll use cardboard in stubborn weedy areas as the first layer of mulch with woodchips on top. 

Use cardboard under wood chips for stubbon weedy areas, like those bordering grass.

There is no such thing as too much mulch in my garden. You definitely don’t want to see any soil through the mulch or that’s precisely where the weeds will set up shop.  Mulching is one of the most important techniques in creating a low maintenance garden that also looks neat, tidy and beautiful. 

What other questions do you have about mulch? Leave them in the comments below and I’ll take some time to answer them.

Megan Cain owns The Creative Vegetable Gardener, a Madison company that designs and installs beautiful gardens that produce lots of food. Over the past 10 years she has taught hundreds of kids and adults how to get their hands dirty in the garden.

Comments [8]

Stefanie | June 12, 2013

Complete novice gardener here!  When do you mulch ie how tall should your plants be or do you mulch after seeds are planted but haven’t yet sprouted.  Thanks!!

Megan Cain | June 13, 2013

Hi Stephanie-

Great questions! My garden is always mulched, so when planting seedlings I just make little holes in the mulch and plant into the ground.  You can see a photo example in my post from last month.  If I am planting seeds, sometimes I separate the mulch to make “rows” so that I can plant into the soil.  Sometimes I just take the mulch off of that section of garden.  You shouldn’t cover newly seeded areas with mulch because the tiny seedlings might have trouble getting through it.  Once the seeded crops get to a bigger and more sturdy size I will mulch around them.

S | June 15, 2013

I mulch almost exclusively with grass clippings, and they work great for me—and are free!  For newer plantings I just mulch heavily with a gap around plants, and as it dries out/turns brown I pull it closer to the plants.  It does break down faster than straw, but (excepting drought) we have nearly a constant supply.

People worry about weed seeds with grass but I find it’s not a problem—I rarely find a dandelion in my garden beds and I know there are seeds all over the place!

Tina | June 20, 2013

I have heard that hay may have seeds in them that you don’t want for your garden versus straw that doesn’t have the seeds.  Is there really a difference?  Also, where can I get straw or hay at a reasonable cost.  I have, for the first time, a large garden 25’ x 50’.  its a large area to cover.  Thanks!

Megan Cain | August 11, 2013

Hi S-  Yes, grass clippings work well for an inexpensive mulch.  You can also let it brown in a pile before putting it on your garden bed.

Megan Cain | August 11, 2013

Hi Tina-  Sorry for the delay in responding.  You are right, you have to be careful of your source of hay and straw.  I used some straw on a client’s garden this spring and it sprouted all over their yard.  So, when purchasing look carefully at the bales for seed heads.  Depending on where you live Craig’s list can be a good source of mulch.  The going rate at garden centers is about $6/bale in Madison.

Amanda | November 18, 2014

I am setting up six raised cinderblock gardens this coming spring . I have a full roll of hay I found I was going to use it to heavily mulch my paths in between. I have heard that if the hay starts to sprout you can spray vinegar on it all if its a path and it will stop it from trying to sprout the seeds.

Megan Cain - The Creative Vegetable Gardener. | November 19, 2014

Hi Amanda- You’re on the right track with heavily mulching your paths! It is true that hay can start to sprout, I had it happen to me last year. Usually people use a vinegar spray after it sprouts to kill the plant. I don’t think it will prevent it from sprouting, but it’s worth an experiment! A little sprouting hay in your aisle is worth it to keep down the weeds I think.

Add Your Comment




Please enter the word you see below

* Fields Required.
Your email will not be shared.
Your website will be linked to your name.

More Articles: