Let’s talk about lasagna (mulch) beds
I love teaching this method because, in my opinion, it’s the second best option behind a truly high quality raised bed mix like our Performance Blend or All Season Blend. A lot of bulk “raised bed” soils are incredibly dense and heavy. They’re built to be cheap, not biologically alive or structurally balanced and plants really struggle with that. Roots get choked out and stay over saturated far too long. If you’ve ever been able to make it to any of our educational events I always talk about the importance of having that ideal air:water ratio in the root zone to allow for proper gas exchange. Ultimately, plants die in these cheaper bulk options and people end up disappointed and redoing them later anyway. Or even worse get frustrated and give up.
That said, we’re all working within different budgets.
If gardening is important to you and you have the means, investing in quality soil is something you’ll thank yourself for every single season. You’ll grow more food or flowers, with less effort, in soil that improves year after year. And all you have to do is fill a raised bed or pot. You spend more money up front for guaranteed results and not having to work or wait for those results.
But if that investment isn’t possible right now and you’re willing to get your hands dirty and be patient, you can build something FAR better than cheap bulk topsoil.
So what is a lasagna bed?
It’s simply layering organic materials that break down over time into rich, fertile, biologically active soil full of tilth.
So you know what to expect after you build this… you’ll get
- Decent results year one
- Much better results year two
- Incredible results by year three
It just takes time for it to mature.
In the photos you’ll see I use a few different things.
1.) Alfalfa hay (when sourcing, ask if it was cut early to make sure there are fewer seeds. Straw will have less seeds but lower nutritional value. It’s a trade off)
2.) Locally sourced manure. I incorporated biochar and some organic amendments into the horse manure already before adding. (be careful and always check for herbicide contamination, look into a simple “bioassay test” before applying)
3.) Wood chips or mulch (great fungal food as you can see in the video)
4.) Old potting soil (I never throw mine out and quickly accumulate a lot of it, even though the nutrients have been depleted the structural parts of that soil are still beneficial)
5.) Biochar (AMAZING home for your microorganisms and nutrient battery. We have plenty available if you would like to source from us)
6.) Organic Amendments (like our dry amendment mix Revive)
All these things are cheap or even free and locally available. Hay and straw are all over marketplace. People are offering up manure for free or incredibly cheap (don’t forget the bioassay test!) Woodchips are easy to get free since tree cutting/brush management services don’t want to pay to dump them. Old potting soil you already have. This can be done SO cheap.
You layer these inputs up to build it up into a raised bed. It will shrink dramatically as everything breaks down. It will become home to all kinds of life like worms (yay for an infinite supply of worm castings), insects (yay for an infinite amount of chitin and frass), and fungi/bacteria/microorganisms (backbone of this system) that all contribute to this productive soil building ecosystem. A larger number of thinner layers tends to work better/quicker but again, a little more work. Free time is hard to find these days so the one I made yesterday is just a handful of thicker layers. Do the best you can with the time and materials you have. Don't overthink it too much.
Then you let biology do what it does best.
One thing to keep in mind, just like when you are composting, is balancing the amount of nitrogen rich (manures and green inputs) with your carbon inputs (wood chips and heavy carbon inputs). Generally 1 part green to 2-3 parts brown works well.
Green Input Examples
- Alfalfa Hay
- Manure
- Kitchen scraps (no meat. no greasy/oily foods. Limit citrus and dairy but generally okay
- in smaller amounts)
- Coffee grounds
- Fresh plant trimmings or grass clippings
Brown Input Examples
- Dry leaves
- Straw
- Wood chips or small sticks and branches
- Untreated sawdust
Over time, all that organic matter transforms into beautiful, living soil that is built with patience more than money. And every year you can keep adding more layers to feed the biological engine that runs this process. Slowly but surely you build an even deeper and deeper bed that is far more valuable than the cost it takes to produce.
It all just takes some time… and a little dirt under your fingernails.
The final video shows you what you’ll end up with if you end up trying this process out!
Feel free to message me with any questions! Hard to cover everything without this post turning into more of an essay than it already.
As I got to the end here I realized I wanted to do a quick description of what a bioassay test is and does. Basically we are wanting to cheaply test if manures are contaminated by herbicides that can persist through the animals digestive system and even after aging that manure. What you do is take a really herbicide sensitive plant like peas and grow it in a potting mix without manure and then some with 25-50% of that manure mixed in. Compare growth rates and look for twisted or abnormal unhealthy growth from the manure based mix. Peas are a good choice due to their sensitivity to these herbicides and will show twisted stems, stunted roots, or weak structure if they are present. If you don’t see any of these you are good to go! Usually takes a couple weeks to see so it doesn’t take too long and is nice to know for sure whether your manure is clean from contamination or not.
