Using Mulch in the Garden: A Comprehensive Guide

I’ll be honest, I haven’t always been a fan of mulch. I went a full 13 years – yes, you read that right – without ever using mulch in my vegetable gardens. I didn’t want to go through the hassle of locating it. I didn’t want to pay for it. I liked the look of bare soil. I thought it wasn’t necessary. Boy, was I wrong!

Everything changed in 2023 when we moved to our new homestead. I knew that I was going to be super busy with the move and less able to dedicate time to weeding my garden. I had heard that organic straw was a great mulch to use for weed suppression, so I thought I’d give it a try.

I hopped on Facebook marketplace, located a local farm, loaded up my truck, and brought 10 square bales home with me. I planned to use half of it in the garden and the other half as bedding in the chicken coop. Great plan, right?

*Disclosure: This post may contain affiliate links to products (including Amazon). I’ll earn a small commission if you purchase through my link, at no additional cost to you! Regardless, I only link to products that I personally use on our homestead or believe in.

Why Use Mulch in Your Garden?

Once I got home, I spread as much mulch as I could, but was only able to get half of it done before I had to get back to moving and unpacking. After just a few weeks, the difference between the two sides of my garden was night and day!

Weed suppression

My original plan was to mulch my garden to help with weeds and it sure did deliver! With the warm weather that we had in June, the weeds absolutely exploded in my new garden bed within just a few weeks (see photo below). New garden beds are notorious for a burst of weeds since they are loaded with weed seeds from whatever was growing there previously.

I was faced with the massive undertaking of tediously weeding the remaining rows in my garden, but… what about those rows that were mulched? Hardly. Any. Weeds!!! Hallelujah! I was so pleased that it worked and was bummed that I didn’t do my whole garden right away.

Once I finally got the rest of the garden weeded, I quickly mulched those rows and hardly had to do any weeding the rest of the summer (except for those walking paths – keep reading to learn more about that part!).

Moderate soil temp & encourage worm activity

Mission accomplished, the mulch solved my weed issue, but that’s not all. When I started to dig around and harvest produce, I also noticed a big difference in the amount of worms I was finding between the mulched and unmulched sides. There were SO many worms under the mulch!

Worms are a huge help in the garden – they improve the structure of your garden soil by munching on large particles and releasing them as worm castings. They also aerate the soil, which allows for better root growth and water absorption. The key to drawing them in is to provide an environment that they like, which is moderate temperatures (they don’t like hot soil!) and lots of organic matter.

Mulch provides these conditions – it keeps the soil temp nice and stable. Less overheating in the hot days of summer and it provides good insulation on those frosty nights at the end of the season. It also protects the soil from erosion and composts down, providing excellent organic matter that those worms love.

Reduce watering needs

In 2023, we had a significant drought in Minnesota, and on top of that, watering itself became a challenge. Our water at our new homestead has off-the-charts high levels of iron, so when I tried to water my garden, my plants and fencing literally turned brown, and plant growth slowed. Uff da.

So, once again, the mulch that I threw down saved the day. It was so effective in retaining moisture that our occasional rainfalls were sufficient enough that I rarely needed to water anymore. It was wonderful! If you’re in a location where it’s frequently dry or if you have water restrictions, definitely consider adding mulch!

Protect against plant disease

I used to have an all-out battle with blight at our last homestead. My tomato plants would shrivel up and often completely die before they even had the chance to produce any tomatoes. Blight is a common soil-borne disease caused by soil splashing up on the leaves from rainfall or watering.

Mulch solves this issue because it serves as a barrier between the plant leaves and the soil. I had ZERO blight as soon as I started mulching – Voila!

Which Type of Mulch is Best?

So, you’ve been hearing me talk a lot about using organic straw and you’re likely wondering if that’s the only option. Nope! While it is my favorite, there are a few other options out there. I’ve upped my mulching game this year and I actually use several types of mulch now. Let’s dive in to find out what it is!

#1: Organic straw

Alright, let’s talk about my favorite garden mulch first: organic straw! I love it for multiple reasons – it’s relatively easy to find, inexpensive, composts well, looks nice, easy to remove (if needed), and it works! Plus, it also makes for some awesome chicken bedding, so I buy bales in bulk and use it in both my chicken coop and garden.

Is straw the same thing as hay?

Nope! Straw is the leftover stem bits after the top grain is harvested (usually wheat). While some seed heads will be leftover by accident (which can sprout as “weeds” in your garden), it’s pretty minimal compared to hay. Hay is grass that is cut and dried for animal feed. Since it’s the full plant it’s typically loaded of those seed heads!

A word on sourcing straw

This part is super, SUPER important. Please don’t pick up any random straw bale that you find at your local landscaping center. Straw is commonly sprayed with herbicides and that is not something you want rubbing up on your plants and food!

I’ve heard one too many horror stories from gardeners killing their plants by using conventionally grown staw. Eep!

So, take your time to source some organic straw from a farmer you trust. How do you do that? I’ve personally had good success on Facebook marketplace. While I’ve had to drive an hour to get there, it was worth the effort.

Are there any cons to using straw?

Yes, it’s not a perfect solution, but it’s close! Straw can contain some residual seed heads (usually wheat) which can germinate and voila, you’re growing some wheat grass. The good news is that those seedlings have germinated within the staw, not the soil, so they are super easy to pluck out.

#2: Wood chips

Wood chips are a new type of mulch that I’m using in my garden this year, and I’m already super impressed! I’ve chosen to use it on my walking paths and garden perimeter, not around my plants. The reason for this is that wood chips are more permanent than straw, so be choosey where you use it.

The best way to use wood chips

Let’s say you mulch your tomato plants with wood chips one year and the next year you want to seed carrots. That won’t work out so well with all those wood chips in the way and they can be a bit of a bear to move.

Because of this stubbornness, that makes wood chips an awesome solution for walking paths! Wood chips can also pull nitrogen out of the soil as it starts to compost down, so that’s another reason why I prefer to keep them on the walking paths vs directly around my plants. However, this risk is quite a bit lower if they are just on top of the soil vs worked in.

This is the type of mulch that I do not plan on removing in the fall as I want year-round protection here (plus, it would be an incredible amount of work to remove it!). I’ll just keep topping it off with fresh wood chips each spring, or whenever it starts getting bare. It will eventually compost down, but not for a while!

Where can I get wood chips?

Wood chips are almost as easy to find as straw, however, you want to make sure you’re picking the right stuff. Stear clear of those bags of landscaping wood chips that are dyed and often sprayed with herbicides. No thanks!

Instead, find a source of plain ol’ chipped-up trees. If you have some cleanup to do on your property, you can rent a wood chipper and make a fun day of it! Otherwise, try calling around to local logging or tree trimming businesses – they are often overloaded with mulch and happy to drop some off. I’ve also heard good things about Chip Drop!

#3: Grass clippings

Do you know what I love about this option? It’s FREE! Heck yes! If you have a bagger on your mower, start saving up your grass clippings! However, there are a few things to keep in mind when using grass clippings as mulch in your garden.

If you’re like me and you wait a while between mowings to the point where the grass or any other “weeds” have gone to seed, you’re going to end up dumping ALLLL those seeds straight into your garden. Uh oh! So, I would only recommend doing this if you’re pretty prompt about mowing.

Lastly, you might end up burning your plants if you add fresh grass clippings. That’s because it’s green and will start composting, which is a hot process. To avoid this, spread out the grass clippings for a few days to dry before adding them as mulch.

#4: Hemp

I’ve become a real lover of shredded hemp stalks when it comes to chicken coop bedding and mulch in the garden. However, there’s one big caveat to this… PRICE. Whew! It sure is expensive! It’s also pretty difficult to track down. I’ve used it in small applications when I’ve received free samples, but the price is too high for me to justify using it on a large scale, unfortunately.

*If you want to give it a go, I’ve found an awesome company located right here in MN! They are called Hemp Acres and you can get 20% off your order with my discount code THRD20!

#5: Compost

Compost is another great mulching option and this is one that I have tried here and there over the years. At our last homestead, we had incredibly sandy soil (pretty much beach sand!), so it was challenging to keep the nutrient levels up. Therefore, I would top dress with compost throughout the season to give my plants a boost.

The second way to use compost as mulch is what I do every fall. Once I clean up the garden and remove the organic straw, I spread a 1-2″ layer of compost on top of my planting rows. This provides a great protective layer throughout the winter. Then, I work it in the following spring!

#6: Leaves & Pine Needles

I love being able to use the things that I find in nature. Not only is it free, but there’s something satisfying about tying your homestead into the rhythms of nature. Fall is a great time to gather fallen leaves and mulch your garden for winter protection – especially around your perennials! This may not work so well if you’re in a windy area, but it’s great on our wooded property.

Pine needles are another favorite of mine, especially for mulching around my acid-loving blueberries. That’s because pine needles are acidic, however, they don’t have a large effect on soil pH since they rest on top and once they compost down they become quite neutral. So, don’t let that scare you away from using them!

#7: Living mulch

Ever heard of living mulch or cover crops? This one is a bit trickier to manage, but it works well if you can pull it off! It involves utilizing a low-growing crop with shallow roots to provide a living cover of the bare soil around your main crop. You can even do a “chop and drop” allowing them to compost in place.

Another option is using something that vines like squash or pumpkins. I LOVE planting my butternut squash and cinderella pumpkins in the middle of my corn patch because it provides a lovely living mulch for my corn. Then, as the temps dip in the early fall, the corn provides some cover for the squash. A win-win!

#8: Cardboard

Oh, cardboard. I have a love-hate relationship with it. It saved the day in my garden when we first put it in and the weeds took over and I needed a solution FAST, but it’s not something I want to be using year after year.

What I like is that it’s readily available and is a great way to use up boxes that you may have lying around. Cardboard is cheap, easy to cut to shape, and lay down, and it’s a very effective weed barrier.

Cardboard being used in the walking paths of a large in-ground garden — You can see the cardboard I was using for the walking paths in 2023.

What I don’t like about cardboard is that it can introduce some unwanted particles into your garden. Cardboard can contain glues, inks, tape, and even PFAS. No thanks! It also shreds into pieces when it starts to break down, which can blow around and make a mess in a hurry.

#9: Plastic mulch

While plastic is a common option in our modern world (hence why it made it onto this list), this is not one that I recommend. I can see its virtues – it warms the soil, it’s very effective at weed suppression, and it’s easy to find at the store. However, plastic is generally a no-go for me when it comes to my soil health and growing my food.

Watch Me Add Mulch To My Garden!

Tips for Adding Mulch to Your Vegetable Garden

When it comes to laying down the mulch, there is an art to it. You don’t want to just throw it down everywhere and at any time. While I LOVE mulch, I choose only a thin layer at certain times and there are instances where actually I choose not to use mulch. Here are my best tips!

Tip #1: Add the right thickness

Getting the thickness right can really make or break your experience with mulch in your garden. Too thin and the weeds will bust on through the mulch and you’ll be left battling not only regular weeds but weed seeds from the mulch. Double bad! Too thick and the soil will remain too damp and cool, which can lead to disease and root rot.

The sweet spot is to add 3-4″ of mulch around your plants. This will provide an effective barrier without overpowering the space. If you find that the weeds are starting to grow through it, add a few more inches. The only exception to this rule is my potatoes. Instead of hilling with soil, I hill them with a very thick layer of mulch! It’s super easy and works well.

Then, there are times when I only add a very light layer of mulch and that’s when I first lay down seed. It can be tricky to get those seeds to germinate since they need consistent moisture (especially those finicky carrot seeds!), so adding a light layer of mulch can really help!

However, those seedlings will also need light, so if you pile on a thick layer they’ll just get smothered and die off. So, I start with a thin layer, then once the seedlings are a few inches tall I start building up the mulch layer around them.

Tip #2: Add mulch at the right time

If you live in a cold climate like I do in Minnesota, this one is KEY! Cold soil temps are a problem when wanting to get our hot-loving plants (tomatoes, peppers, squash, cucumbers, etc.) into the ground. If you mulch right away, then the sun won’t be as effective in getting that precious soil temp up.

I mulch most of my plants right away, but I wait on mulching my hot-loving plants until we’ve had a string of nice warm weather (80+F) – usually late June. That way that dark soil really has a chance to soak up that heat before it gets covered up.

How much does mulch cool the soil? I’ve done some experimenting with my soil thermometer and have found that mulched soil is about 6 degrees cooler than mulchless soil. Not a drastic difference, but enough to give it some consideration!

Tip #3: Keep an eye out for pests

Mulch can be a wonderful help in the garden in regards to soil quality, moisture retention, and weed control, but it can also provide a cozy home for pests to take residence in. While I haven’t personally noticed an increase in pests, I’ve heard this from time to time from other gardeners.

So, be on the lookout, and if you notice a spike in pests you’ll be faced with a dilemma. Keep the mulch and engage in some (hopefully organic) practices to ward them off or remove the mulch. Personally, I would try option #1 first. You already went through the work of getting the mulch down and your garden is benefiting from it being in place. If all else fails, remove the mulch.

Tip #4: Clean up vs compost down

This is an ongoing debate and every gardener treats mulch differently at the end of the season:

Some like to leave it in place in the fall, then add a fresh layer on top next spring while allowing the lower layers to compost down.
Some like to leave it in place in the fall, but remove it and replace it with a fresh layer in the spring.
Some like to remove it in the fall and then add a fresh layer in the spring

What do I do? I’m in camp #3 – I remove the straw in the fall and then add a fresh layer in the spring. Why do I do this? I have a healthy fear of plant pests and diseases.

While I know my soil would likely benefit from a layer of thick mulch in the winter (especially during our brutal MN winters), I worry about harboring issues into spring. Instead, I add 1-2″ inches of compost in the fall and that serves as a form of mulch throughout the winter until I work it in the following spring. So far, so good!

Watch me do spring garden prep!

The only exception to this rule are my perennial vegetables and herbs. I always mulch them with a heavy layer of organic straw (or dried leaves!) to protect them from winter damage.

Plus, since I use organic straw as mulch, it composts down into some lovely compost! I love being able to pile it all up in my compost pile to give it back to my garden in another way the following year. Plus, the chickens just LOVE scratching around in it for any leftover garden goodies and bugs.

Using Mulch in the Garden: A Comprehensive Guide