Mulching Your Garden Part 2 — How to Mulch Your Garden

It’s time to talk mulching again!  Last week I gave you my opinion in “Why Mulch Your Garden?”. . . this week I’m going to talk about HOW to mulch your garden.

The first consideration when mulching your garden is what to use for the mulch.  As I stated before I prefer organic mulches, so I immediately discounted plastic or “weed barrier” type cloth.

In my area some of easiest mulch materials to find are hay, leaves, wood chips, grass clippings and compost.  Each has it’s points:

1.  Hay is usually pretty easy to find in an agricultural area.  Since it is for mulch and not for an animal to eat you don’t have to buy “fresh” hay-it can be old, even starting to rot.  Most farmers are happy to give you a reduced rate or even provide it for free if you are lucky.  Hay is organic so it will break down and actually acts as a soil amendment as well as a mulch over time.  There are some issues to be concerned with using hay.  Some farmers may spray hay fields with fertilizers or pesticides.   Hay also tends to include some weeds and the seed heads for the hay–so you can be introducing those into your garden.  Straw is basically hay where the seed heads have been eaten off by animals-if you get true straw then you don’t need to worry about weeds. 

I made the decision to use hay because it was available and free. Luckily in our area most farmers just let the fields grow and cut it for hay-so I didn’t have to worry about fertilizers or pesticides.  So far I have not had any seed heads sprout, and I figure that next year I’ll just mulch on top of it again with more mulch and hope that it suppresses any seeds.

2.  Leaves are usually free and plentiful in the fall.  Most of the time the neighbors are thrilled if you want to take their leaves away for them!  Do be aware that whole leaves can mat down and actually prevent water from permeating–chopped up leaves are better-so you probably want to run them over with your lawnmower first.  You don’t want to ever use black walnut leaves-they are allopathic, which means they prevent the growth of other plants.  You should also be aware that trees and therefore their leaves can be bio-accumulators.  Since they live so long they tend to soak things up from the environment and then store them in the bark and leaves.  So if lots of folks in your area spray their lawns with pesticides and fertilizers than those things may be present in the leaves.

I did compost leaves last fall and used them as mulch on the garlic bed and on top of the overwintered carrots.  Again-one of the benefits of being in a small village upstate is that I don’t know ANYONE who uses chemical fertilizers on their lawns–it’s pretty much a “mow whatever grows there naturally and call it a lawn” kind of place.  So I’m not worried about chemicals being in my leaves or the leaves I snag from neighbors.

3. Wood Chips are another readily available mulch.  They are sold by the bag at most major box stores.  You can usually buy them by the truckload at various garden centers (our AGWAY sells them for $35 a scoop-and that’s a scoop from a bucket loader).  If you are purchasing wood mulch then avoid the “dyed” and colored mulches.  You probably don’t want to add those chemicals to your garden!  As a much more frugal option, many municipalities have free wood chips available to residents–it’s the chips they make from the tree branches they trim on roadways and such.  You can even rent or buy a chipper and chip your own.  Of course just like the leaves, you want to make sure you don’t use walnut or wood from areas where it might have accumulated pesticides.

Many people are “scared” of wood chips because of the belief that as the wood chips break down they tie up nitrogen and that could steal nitrogen from the soil (remember nitrogen is one of the main things plants need to grow).  However my feeling after reading a lot of sources and actually having wood chip mulch for a season is that the only place the wood chips are using up nitrogen is in the very top layer of the soil where the wood chips touch the soil.  Now, if you were to till the wood chips into the soil THAT would cause a problem!

I decided to use free wood chips from a local municipal source.  Walnut trees just aren’t that prevalent that I felt like I needed to worry about it, and again, in this area pesticide use is not as much of an issue.

4.  Grass clippings are available whenever you cut your grass.  Of course the same issues with fertilizers and pesticides can be present.  You may not have enough grass in one go to mulch your entire garden–but if you keep raking up the dry grass clippings (not fresh-give them a day to dry) you can slowly add the mulch over time.

I used grass mulch as an experiment on one row of my back garden.  It packed down very flat and has done well.

5.  Compost is a great mulch, it adds a lot of nutrition and organic matter to the soil and smothers weeds.  You can make your own compost-but few of us have the ability to make enough compost to actually mulch a garden.  Some lucky areas have municipal compost available–so you should use the same cautions as for wood chips and leaves–chemicals can be present.  Nurserys and garden centers also sell compost.

I don’t have enough compost to use it as a mulch.

My main mulches are wood chips and hay:

Now on to laying your mulch.

Since you want to retain moisture, if at all possible mulching a day or so after a rain would be optimum.  That wasn’t possible for me this year.

Your other main goal is to suppress weeds.  To do that you should start with a weed free area.  I hand weeded the garden before mulching.  To be extra weed resistant I laid down wet newspaper first and then placed the wood chips on top.

If you choose to use newspaper as a weed barrier (3 pages thick, black and white, not glossy colored please!) then you really should wet it first to ensure it doesn’t act as a wick and pull moisture from the soil instead of helping to keep it in!  You can lay it all out and then squirt it with a hose until it’s drenched, or you can do as I did and fill a bucket with water and dunk the paper in before laying it out.

I worked a section at a time and wet the paper, laid it down then covered with about an inch of wood chips, ensuring that all the paper was covered (again-little sections sticking out will dry out and then act as wicks).  If you aren’t using the paper I’d make the chips a bit deeper, say anywhere between an inch and two.

For the back garden I used hay and no paper.  The area on the right you can see is laid with a nice thick layer of hay.  I just pulled of “flakes” of the hay and sort of fluffed it up a bit then laid it down so it was 3 or 4 inches thick.  The row on the left is actually covered with grass clippings (see how it looks flatter and smoother?).  Here’s a closeup of the grass clippings:

I did not use any kind of under layer of paper on the main garden-I knew that the places that were walkways now might be rows or blocks of garden as the season progressed. . . I wanted to be able to easily reach the ground underneath for fall planting and such.

When you are spreading hay you will want to wear some gloves.  Trust me, you will avoid a million scratches and pricks and your hands will thank you.  I wore these awesome ones that my client Fields and Lane gave me after I worked on a campaign organizing bloggers for them.  They are their Forester gloves, and they are AWESOME.  They do cost about $27 but they will last you a long, long time, and the goat skin leather is soft and can be wet & goes right back to being flexible.  But back to the mulching. . .

My tomato garden has some terrible weeds, so I did the hand weeding thing then in the walkways I laid down thick brown paper bags before laying the hay in the same manner that I did in the main garden.  I knew that the tomatoes would be growing right up until the fall and that I would not be adding or changing any rows there.

I think it looks rather nice all mulched up.

So how has it worked?  Very well!  The mulch has kept moisture in the soil-when you pull back the mulch you can see that it is a darker color underneath. Worms and toads are living in there and I’m finding plenty of worm casings and other good for the garden things.

On the left I pulled back the mulch to show you the moisture. The ground on the right was just planted 2 days ago and so is bare. See how much drier it is?

With the mulch in place I have not had much in the way of weed growth in the center of the garden.  Within the rows themselves where ever the mulch has been moved aside to make room for the plants weeds do try to grow.

Anything that spreads by sending out runners tries to creep in over the top of the mulch from the outside edges of the gardens.  Like wild strawberry and ground ivy:

So occasionally I have to pluck out a few weeds around the base of my vegetables, or pull up some creepers that are trying to sneak in.  That is much, much less weeding than I’ve had to do in previous years.  All in all I am extremely pleased with how well mulching has worked on my gardens, and I plan to continue using mulch yearly-most likely just adding more layers on top of the current one!

If you would like some more information on mulching, Organic Gardening has a nice “Mulch Materials Research Report” that you might enjoy.

So what do you think? Have I convinced any of you to try mulching your garden?