Making Organic Soil For Raised Garden Beds (success)

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Raised garden beds

Raised garden beds are fantastic for a small to medium sized yard, and while they are good, obtaining good quality soil to fill a bed can be costly, often the soil quality is doubtful.

Sometimes it can even be downright terrible. This article is about bypassing all of those issues and making the best soil money cannot buy, all from the comfort of your own back yard.

We live in the tropics of far North Queensland, Australia. We have two very distinct seasons, being the Wet and the Dry.

Wet season can bring 3 mtrs of rain while the dry season can deliver a few 10’s of mls for a given month. It really is a set of extreme situations.

Understanding the dynamics of heavy rainfall on soil led us to start using raised garden beds for the annual plantings of vegetables.

Heavy rainfall leaches the minerals and trace elements from the top layers of the soil leaving them depleted of key nutrients that most plants require…..particularly when you want to plant lots of things in close proximity to each other. We do this with ginger and turmeric as this post titled “can ginger and turmeric be grown together?” shows.

The use of raised beds allows us to reload the nutrients and fine tune each bed to suit a particular crop. It is also far easier to top up a raised be each year with naturally made quality soil instead of throwing a bunch of store bought fertilizers at a ground bed.

While that might work for some, we find the ingredients are sometimes suspect and the cost comes out of your pocket. The whole idea of self sufficiency is about saving money by not spending it on something that we can do at home, with a higher quality to boot. This can include building your own beds, and “What is the safest material for organic raised bed gardening?” covers some of the details.

What is Organic Soil?

The words “organic soil” seem strange when soil is all around us. However, all soils are not equal. Some soils are bereft of nutrients while other soils are bursting with life. What makes them different?

To get the best results that are reliable and consistent we have partnered with a few feathered friends. We help them do what they love doing, and that is turning soil over by scratching it all over the place.

Organic soil contains life supportive elements. It is rich in natural compounds like decaying leaf litter, residue from rotten logs courtesy of the activities of fungus.

It is loaded with carbon. It also holds nutrients tightly, but in a way that plants roots can access them easily. Sometimes we have to start with poor soil and build it up, and “what is the best soil for organic gardening in raised beds?” details how to arrive with organic soil.

Organic soil holds moisture well instead of allowing the water to pass through too quickly. All of these attributes are required if you want soil that will support your plants. The better the soil, the heavier you can plant, keeping light availability in mind.

Organic soil should not contain man made fertilizers or soil additives. It needs to be completely natural. You can look to the natural composting processes that make good soils and these are touched on and explained in these articles titled “growing ginger” and “how to care for turmeric plants“.

Can Organic Soil Be Made?

Yes it can be. Understanding the process of soil building in a natural setting is the best teacher.

If you have a spot in the yard, maybe under a tree in the shade where a good bed of litter has accumulated from fallen leaves, have a scratch around under the litter where the soil surface is and look at the soil color.

Note the bug activity. What you are seeing is the slow motion process of soil creation. It can be very slow if left to its own devices.

We can speed up the process with some simple steps. Organic soil can also be maintained at a good state of fertility once you have it and “how to maintain organic soil in raised garden beds” explains the process.

Making Organic Soil At Home.

There are a few methods for making great organic soil and we can go into a few now.

There is a fast method that requires a fair bit if input from you….call it sweat equity…….and there is a more gentle way that involves our favorite critter, the chook, or chicken for non-Australians.

The fast method is the process of creating compost and adding it to your raised garden beds every time you plant them out. If you don’t have chickens then this method fits you.

This article is not going to go into detail on how we do this, however, compost for self-sufficient gardening does. This post is just about the partnering with chickens to get the best soil possible for your situation.

The best part of this process is that as the years progress and the garden gets more and more productive, the chickens get to feast more on the vegetables that we don’t want.

They may have splits from unseasonal rain, they may have been attacked by insects and have larvae within. The leafy greens are always a favorite.

The point here is that very little goes to waste and even if the chooks don’t eat the scraps they break them down by scratching in their pen.

We don’t let the chickens out that much as they can get pretty excited in the mulch under the trees and they leave the place in a heck of a mess. The garden can’t cope with that on a daily basis so we take the forage to them most days.

There is another reason for having them locked up though, apart from avoiding the strewn mulch piles.

Chickens as Compost Factories.

Keeping the chickens in a largish pen allows us to contain and harness the behavior of the chook to create compost.

Because we give them all sorts of food, many good viable seeds are scattered and buried in the chook pen soil. A great example of this is excess papaya, or pawpaw.

We have a bunch of these trees/plants on site and often have far too much fruit to handle ourselves so the chickens get the whole fruit intact.

They love the stuff. They don’t seem to be taken by the seeds though, so these seeds end up everywhere as you will discover.

Here is where site design gets interesting because the location of the pen matters. Our yard or block is only 1/4 acre so every bit of space matters.

The site has a slope to it with the high point at the rear left and the lowest point at the front right. There is about 1.5 mtrs fall overall. We have the chook pen at the highest point and this is for several reasons.

The main reason is for heavy rain. We need to keep the nutrients on site for as long as possible so having the pen near the highest point allows the flood event to fertilize the yard through gravity.

That takes care of the perennials that we have.

The next reason, and probably the most beneficial of them is because of the gradual slope, the soil that the chickens excavate within their pen while hunting for worms and things ends up at the low side of the pen.

The soil we want to take from the pen ends up right at the gate. I don’t have to rake it up at all. I just get a wheelbarrow of soil at a time and let the chickens build it back again.

The more scraps we give them them, the more bugs there are. The more they turn the soil over, the better the soil becomes.

The better the soil, the more we can grow and the more scraps they get…..it’s an engine.

This is the primary reason the pen is where it is. Chooks scratch stuff down hill. You can take that to the bank.

Base Soil For Raised Garden beds

So now we get to the nitty gritty of raised garden beds. A reasonably sized bed can take a cubic metre of soil and it’s unlikely you will have that much in the chook pen.

I know we didn’t. We were lucky that before we started down the self sufficiency path we lived a pretty standard urban life.

We worked away from home and had the weekends off. We put in a pool. We landscaped the yard. We were very average.

But we were smart enough to keep the dirt from the digging the pool and used that in the landscaping around the boundary. It was poor quality soil…. aka dirt.

Fast forward to now and this is what we have done and are still doing. We are re-designing areas of the yard where there is zero productivity and putting in raised garden beds.

The dirt from the pool is 3/4 filling the beds before we top them up with the best soil in the world. We can do this because the plants only need the top 6 inches or 150mm to access the nutrients in the soil.

Because of the soil being loose in the beds it settles each year and needs a top up before we plant it again. This works in great with the process of the chicken pen activities.

Over a few seasons we end up with rich deep organic soil in the raised beds.

If you are considering raised beds and are looking for fill for the base, then maybe contact your local pool builder and ask if they can spare a load of dirt from the next pool the dig. It’s worth asking. If you need help picking what material to use in your garden beds, “Why use corrugated steel raised garden beds?” may help some.

Bonus Free Seedlings

Further up the article I mentioned about about the seeds from the veggies and fruit that the chickens get given.

Most don’t get eaten, and many don’t survive the trauma of being kicked from one end of the pen to the other.

But enough do turn up in the wheelbarrows of soil that I fill the beds with to give a bonus for the season. We rarely plant out pumpkin seedlings now.

They self germinate wherever they decide.

If the spot is suitable we let them do their thing with some guidance, and we pull the others out and return them to the chook pen. We will transplant at times if we have room.

We get given the odd pumpkin from people who have too many and if we can use them and we are short ourselves we will take them. The seeds end up in the pen with the others.

After they have taken a trip in the wheelbarrow and end up in a raised garden bed, they might germinate and grow if the spot is suitable for us, and then cross pollinate with other types growing at the time.

This means we have a weird strain on site that is always evolving, but the taste is great mostly and the plants are becoming very hardy and reliable croppers.

So in conclusion, to become self sufficient requires work. Some of that work can be outsourced to willing partners in the form of chickens. They will happily create some of the best quality soil you can imagine…if you let them. We also team up with the chickens to make designer poo that is seriously good. We have a post titled “improve your garden soil with rock dust and chickens“. We recommend it as a next step from this post.

The bonus of eggs is just the icing. You can then get on with growing some of your food in raised garden beds. It’s a real win-win.

Article by Tim Blanch for TheTropicalHomestead.com. He is a qualified Permaculture designer.