DIY lasagna beds- cheaper and cooler than ever!

The biggest challenge I've faced with urban gardening has always been lack of resources. Living in a city environment often leaves you short on amenities necessary for a healthy farm, namely land, soil, and access to compostable materials. Not to mention lack of money.

Raised beds are generally the way to go with city gardening. There are many advantages: you get to choose the quality of the soil, fewer weeds, less bending over, motorized tools not necessary. Planting in ground is always a possibility, but you have to deal with the annoyances of infertile or poisonous soil, compacted ground, debris, and hours of labor with hand tools. With a garden like Roots and Rays in Chicago (pictured left), raised beds are a necessity. The entire city of Chicago is a brownfield, i.e. toxic ground totally unsuitable for growing.

But raised beds cost money.

There's the lumber, the hardware, and then the big expense, the soil. In Tallahassee, mushroom compost costs almost $40 a yard, not including delivery. One yard barely fills a bed that's 8'x4'x1'. What's a community gardener supposed to do?

Build lasagna beds!

Lasagna beds accomplish the same effect as raised beds, just without the lumber or the soil. They are much cheaper, but a little more of a pain in the butt to get together.

Like the name suggests, lasagna beds are layered planting beds. It's also called sheet composting. Following the rules of compost will give you a decent lasagna bed. Rules of compost: good mix of green material and brown material, layered on top of each other with plenty of aeration and moisture.

I just built a lasagna bed in my back yard to expand my garden. We also used lasagna beds our first year at Roots and Rays. Here's how you do it.

First layer- Cardboard to help protect against possible toxic leaching, and to kill whatever's growing under your future bed.

Second layer- Browns of any sort. Browns are organic materials consisting of tree material. They are composed of mostly carbon. Leaves, hay, paper, woodchips, or sawdust are all brown. Paper, woodchips and sawdust, however, are too highly concentrated with carbon and will slow down decomposition in your bed, so try and stick to leaves or hay.

Third layer- Greens of any sort. Greens are organic materials consisting of verdant plant material, like grass clippings, weeds, food scraps, or animal manure. You don't want as many greens as you do you browns- too much green makes your bed stink. In my bed I used unsifted compost from my Earth Machine .

Fourth layer- Peat moss or coir (coconut hull fiber). Peat moss and coir are both sterile materials and add no extra nutrients to help your plants grow. However, they are excellent for helping to provide drainage and aeration to your bed. They are an added cost, and I've had good success using peat, but you can try for yourself if you think you really need it.

Next layers- Browns, greens, peat. Each layer should be 4-6 inched thick. Repeat until your bed is at least 18" high.

Top layer- Topsoil or compost. The nice thing about lasagna beds is that you can plant in them right away, even though the decomposition hasn't happened yet. As long as you have a fertile surface material, your seeds or transplant babies will have an excellent chance of survival. As they grow they will be fed by the nutrients released in the sheet composting process.

There are some downsides to lasagna beds. First of all, because of the nature of composting, your raw materials will shrink as the composting process happens. You will lose volume to evaporation, runoff, and decomposition. You will have to add layers to your pile every year.

Also, you somehow have to find a bunch of dry leaves, hay, manure, or compost. Imagine trying to collect those things in a neighborhood without trees, and without a truck! That's how it was in my neighborhood in Chicago. It sucked. I did strike it rich one day in Pilsen when I found four trash cans full of bales of hay in an alley behind the Jumping Bean. I borrowed Emily West's car, a 20 year old Buick named Miss Kitty, and packed the back seat full of hay with the help of the guys working in the illicit car garage in the same alley. I did spend a lot of time vacuuming out that back seat. However, we had plenty of hay to build our first beds at Roots and Rays.

Now that I'm in Tallahassee, it's easier. In the spring the live oak trees are putting on new leaves and shedding the old, so there are plenty of bags of leaves on the side of the road ripe for the picking. I do have a pickup truck now, so my life has improved dramatically in the area of roadside scavenging. Also, I've visited a horse ranch in Monticello with a giant manure pile and a giant tractor with a front end loader, so I can fill up said pickup truck with as much manure as I want.

But if you don't have the luck to have access to such things, don't despair! Even with a little bit of cash, lasagna beds are possible. Your biggest expense will be peat moss, costing between $12 and $15 for two cubic feet. This will get you about one layer in a reasonably sized bed. Home Depot will often offer discounts to ripped bags of soil, so do your best to collect those bargains. Bags of leaves emerge on curbsides in the fall, and it doesn't hurt to pick them up whenever you see them. Homemade compost is a lifesaver, so make sure to have some on hand when you start your project.

Springtime is an exciting time for any garden project, so if you're looking to build a new bed or expand on what your already have, try a lasagna bed. You'll love it, I promise.