No-Till Soil

I grew up on a grain farm. Growing up surrounded by farming, you become innately aware that there is a season and a time for everything. Seeds get sown in the spring. Crops get tended in the summer. Crops are harvested in the fall. After the harvest, the fields are tilled and turned under to prepare them for next spring’s seeds. This made sense. 

It wasn’t until I became more of an avid outdoor adventurer in my twenties and thirties that I began looking at nature a little differently. The most lush environments that I ever found myself in were the ones when I was buried deep in a forest somewhere. The forest floor was abundant with life and the springy, hummus-y soil was incredible to walk on, to touch, and to dig my fingers into. It was on one of these forays when the idea first occurred to me that the forest floor grew lush and abundant without the annual tilling that I had accepted as a part of the growing process. The seed stuck (pun intended) and when I first started growing crops commercially I began to look into a method I had heard of called No-Till. 

I didn’t start with No-Till methods right away. The particular piece of land that I grow on was a hay field that hadn’t been touched in approximately 30 years and there were a LOT of perennial weeds. Because I hadn’t fully researched No-Till at that point and because I was under a timeline to get the ground prepared for planting as quickly as possible, we tilled the ground. I don’t regret doing that and given the situation, I would do the same thing if I had to repeat it. However, now that I am in a position to use No-Till methods, this is the system that we use to prepare a new patch of ground for planting. 

So what is No-Till?

Well, it is exactly that. No-Till is a practice in which the soil is not tilled so that the biology of the soil structure and the layers of the soil are completely retained. In the forest, the leaves that fall from the trees and the plants that die down every year are left to decompose on the surface of the soil. The earthworms, bacteria, and microbes begin their work digesting and breaking down these plants. As the years go by, every layer is broken down even further and a new layer is formed on top. Given a few years, the soil starts to become much richer in organic matter. It retains more water and is lighter and fluffier in texture. If you think of soil in the terms of a forest floor, you can start to see how soil develops layers. Each layer of soil from the surface down has a different purpose and attracts different life forms living in it. 

When soil is tilled, one of the things that happens is a disruption of the soil layers. This sounds like it might not be a big deal but imagine what happens when an earthquake effects a city. Imagine the buildings that are knocked down. The materials strewn across the city streets. The people that are homeless and possible casualties. All of the materials that once created that city are still in the city. But they are no longer in the same place, or providing the same function. It will take time for the residents of that city to clean up the debris, put everything back in order, and complete the building process again before the inhabitants of that city can carry on with life as it was before the earthquake. 

It turns out that tilling the soil has the same effect on the soil inhabitants as it does on our hypothetical city dwellers. The contents of the soil, the building blocks, all still exist after the plow has been through, but the structure has been destroyed and the inhabitants have a lot of clean up to do before they can get back to doing their jobs with any efficiency. Not to mention the loss of life that will have occurred from the mechanical process of the tilling (worms cut up, microbes drying up on the surface). Our hypothetical earthquake ravages our city dwellers every single time the plow or rototill passes through. Plowing multiple times within a season keeps our city dwellers in a constant state of emergency, not to mention the loss of life that occurs each time. 

Soil biology has been overlooked for years. It has only recently  begun to be researched and as such, there is so much that we still don’t know about soil. What we think of as an inert substance that is a medium to keep a plant in place on a windy day, is actually filled with an overwhelmingly large and diverse life force. Scientists have only recently started to identify the vastness of the life.

Bacteria, protozoans, arthropods, fungi, archaea, and nematodes! Oh my!

When you hold a handful of soil, you are in fact holding hundreds of thousands of life forms. These life forms are responsible for creating soil structure, breaking down organic matter into forms that plants can use as nutrients, and much, much more. Fungi, for instance, forms a symbiotic relationship with plant roots that allows both to function at a higher level than they ever could on their own. 

The functions that soil performs and the relationships between soil and the plants that live in it are just beginning to be researched. And there is so much more to learn. 

In the meantime, I wanted to share the process that we use here on the farm to prepare a new patch of ground for growing. 

There are a couple of methods that can be used for killing back an existing crop (weeds or a cover crop) but the one that we employ most often is called Occultation. 

Occultation is, very simply, the blocking out of the sun. If you have ever left a bucket or planter on the grass for a few days, you will notice that the grass beneath it is yellow when you pick it back up. If you were to leave that item on the grass long enough, the plants below will starve from lack of sunlight (sunlight=photosynthesis=energy for plants). After the plants have died, the soil life begins to decompose the dead plants. 

We use a large black tarp for occultation in the field. The black tarp traps heat and speeds up the entire process of decomposition. In the heat of the summer, a patch of field can go from grass/weeds to ready to plant in as little as 6 weeks time. When it is cooler outside, it can take as much as 6 months to complete the process (ie over winter). The tarp also traps moisture beneath it which forces any weed seeds on the surface of the soil to germinate. These germinated seeds will then die out due to lack of sunshine. This process helps to clear the top surface of the soil from unwanted weed seeds before we plant. 

Before Occultation. This fall rye cover crop has died back after it was cut down in the summer.
During Occultation. This large black tarp is weighed down with rocks, tires, and pallets.
After Occultation. 6 weeks time in the heat of the summer and the remnants of the cover crop have disappeared. This soil is ready for planting

Weed seeds can lay dormant within the soil for up to 50 years. As soon as they have the right conditions, moisture and light, they will germinate. Every time the soil is tilled, new weed seeds are brought to the surface from the seed bank below. These seeds are exposed to sunlight and moisture and BAM! they geminate. This is why using no-till methods can also help to knock down the amount of weeding to be done on our farm. Once the seeds in the top couple of centimetres of soil have germinated and been killed, as long as the soil isn’t being disturbed below that level, new weed seeds will not be brought to the surface to germinate. That is not to say that we don’t spend any time weeding. We do. But most of the weeds on our established beds are weeds that have been blown in from the wind or have been brought in with compost (more on that in another post). We spend a lot more time weeding our newer beds and every year that goes by, we are able to spend less and less time weeding our established beds. 

There is so much more to soil and to No-Till methods than I can fill one blog post with. If you are interested in knowing more, reach out to me and I can recommend some fantastic books on the subject.


Soil Blocking

Soil Blocking

It’s time to start thinking about seed starting!

There are many ways to start transplants (often called plugs) and the most familiar comes in the form of a plastic 4-pack or 6-pack of seedlings, or as an entire tray of 50-72 plugs. These ubiquitous plastic forms can be found at every greenhouse and big box store from now until the end of June. They are easy to transport from the store to your house and easy to transport from the house to the garden. But when you go to transplant your new seedlings and you pop them out of their plastic forms, what do you do with the plastic plug containers? Do you throw them in the garbage? Do you recycle them? Do you try to save them for reuse? As we commit to trying to reduce the amount of waste in our lifestyles, these are all questions that should be asked. When I was growing for my own backyard, I would reuse the trays from previous years to start seeds in.

Once I started growing commercially, the plastic plug trays quickly became a bone of contention.

The first issue is storage. I’m growing over 23,000 seedlings this year. Even if I am using a plug tray that allows 72 plants per tray, that’s over 300 plug trays that must be washed, and stored somewhere when they are not in use. That takes up a lot of space!

The plug trays are also far from indestructible. I try very hard to be careful with these trays as the cost to purchase is expensive, but even when you think you are taking it easy on them, they bend the wrong way and break. I have yet to make it to a second season with a plug tray in good condition. This results in extra time and risk of them breaking with plants inside, thus dumping the plants onto the ground/floor in transit or with routine moving.

Lastly, there is the outlying cost for all those trays. $$$

I knew after just a couple of seasons of growing commercially that I needed to find a better, more environmentally responsible way of seed starting.

Enter, the soil block.

A soil block is exactly as the name describes. It is a block of compressed soil that acts as both growing medium and container for the seedling. No plug trays means continuing to reduce the mountain of plastic that has become so ubiquitous with agricultural operations.

Although constructed of only soil mixture, the blocks are not as fragile as you would imagine. And once roots begin to fill the soil block they create a completely stable container that can even handle some roughhousing. 

Soil blocks eliminate the expense and storage of plastic containers and they completely eliminate the plastic waste of broken containers.

But the even better news is that this method actually creates a stronger seedling. How?

Plug trays are pyramidal in shape.

A pyramid has only 1/3 of the volume of soil as a cube with the same top dimension. Thus the roots of a plant in a soil block have three times the amount of soil to grow in versus in the same sized plug tray.

Photo credit:
Math Stack Exchange

This means that the seedlings can stay in the soil block for much longer before needing to be planted in the ground as they have more soil and more nutrients to sustain them. This removes the stress of trying to time transplanting perfectly, especially in early spring when weather can cause unexpected delays.

Another thing that becomes obsolete with soil blocks is root bound seedlings. When the roots of a plant in a plug tray reach the edge of the container, they will begin to encircle the edges of the container. If the seedling is left too long, the roots will circle, and circle, and circle. Resulting in a root bound seedling.

Roots of a seedling in a soil block are “air pruned” at the natural edges of the soil block. The roots of these seedlings will push out towards the edge of the block but once they cross into the air they will die off leaving the portion of root within the soil block “pruned”. 

Anyone that knows anything about pruning trees and shrubs will know that when you prune the growing end off of a branch, many more shoots will appear along the branch producing a bushier plant. The science behind this is fascinating.

(Warning: I’m about to geek out here)

The growing point at the end of a branch, shoot, or root is called the apical meristem. The apical meristem produces a hormone that blocks all of the other growing points (buds) further down the stem from growing, thus allowing this top bud to dominate. When the end is cut off of a branch or root, the source of the hormones is also cut off and other buds along the stem will now have the ability to grow. This is what makes a stem bushy. (Like when you’re told to pinch the top off of your basil plant because it will produce more leaves.)

This exact same process is happening at the edges of a soil block. Once the roots push out of the soil block they will reach the air and will be burnt off. Once the apical meristem of the root is removed, that root will branch out and produce many more roots. This means that by the time you are ready to transplant a seedling in a soil block, the soil block is absolutely full of roots that are just waiting to burst out into the surrounding soil. This creates a much bigger, healthier plant, more quickly. 

The other reason that seedlings in soil blocks are so healthy is the actual mixture that is created for the soil blocks.

Unlike in standard plug trays, where the soil mixture needs to be light and porous, in a soil block, we are actually requiring a soil mixture that can be compacted. This mixture is composed of peat, sand, and compost or soil. The mixture not only provides nutrients to the growing seedling but upon transplanting the soil blocks you are adding organic matter to the growing area. A staggering amount of organic matter actually.

Consider this:

2” cubed blocks set out at a spacing of 12” x 12” is the equivalent of applying 5 tons of compost per acre!

So every soil block that is transplanted into the soil is one less shovelful of compost that you need to add later.

Soil blocks save time. They save money. And they save mountains of plastic. This year alone, I will sow over 23,000 seeds to be transplanted into the flower field. And every one of them is sown into a soil block.

Have I convinced you to give them a try yet?

The purchase of a soil blocker is required to make soil blocks. The soil blocker is an ejection mold that forms cubes out of your growing medium. But this is a one time purchase that will last. I have used my soil blockers to make hundreds of thousands of seedlings and they still work like new.

Soil blockers can be purchased at Lee Valley, West Coast Seeds, Johnny’s Selected Seeds, etc.

Please note: I have no affiliation with any of these suppliers and I don’t receive anything if you purchase through them. 

Except maybe the knowledge that I will have stopped a little more plastic from going into the environment.

Change can start one seedling at a time.