Gardening How To: Sheet Mulching

What’s your favorite way to build soil? We know, lasagna and gardening don’t necessarily go together, but sheet mulching or composting (AKA: lasagna gardening) is my absolute favorite way to build soil! It’s also a great way to remove a lawn without backbreaking labor!

Sheet mulching is essentially building rich soil directly in the garden using layers. There are a few ways to go about it, depending on what’s growing in your location – be it grass or weeds – and what your end goal is. If the area is going to be planted, a good balance of Carbon/ Nitrogen is important to help it break down efficiently. Using sheet mulching to create pathways on the other hand, where the objective is to stifle weeds, don’t need as much Nitrogen.

If you are trying to kill your lawn/grass in favor of xeriscaping or creating a new planted space, a brown cardboard base should do the trick.

Be sure to locate irrigation heads and lay down cardboard so there is no grass poking through. Wet cardboard works best.

The next layer can be of straw or leaves. I pile them at least knee high, keeping in mind things shrink.

Wetting these materials down is helpful to keep them from blowing all over . The area can stay like this for 6 months -a year depending on weather/sun exposure/ intended use.

Or you can dress it up on top with compost (this will also help it break down faster) or mulch if you don’t like looking at leaves or straw.  After letting the area sit for some time, add compost and a good planting mix to get growing.

Another great use of sheet mulching is in pathways. Laying down cardboard with wood chips or hemlock mulch on top stifles weed seeds and loosens the soil so that when perennial weeds eventually try to poke through they pull out with ease.

And lastly, don’t be afraid to sheet mulch around existing plantings using newspaper. A great technique for early spring.  Lay newspaper around plants with a layer of compost or mulch and you will see a huge decrease in the amount of weed seeds that would have normally sprouted.  Sometimes that little extra step can save you time later!

Onward hoe!

Written by Heidi Branchesi of Chezem Creek Gardens.