The word compost is a bit confusing, as it can mean two different things, both of which
can be really important when managing a vegetable garden or a growing space.
There is the growing medium or potting compost that is used as a soil substitute for starting
seedlings or for growing plants in pots, and I generally buy in a few bags of this material
every season.
But what I usually refer to as compost is the decomposition of plant debris, animal
manures and other organic material, into a valuable soil amendment.
This bulk material is useful in much larger quantities for adding fertility and improving
the soil quality in the gardens and other growing spaces.
I've made a lot of this type of compost over the years, as it's an essential component
of most of the growing methods that I am trialing, but I never seem to have enough.
I could always produce more by growing and collecting additional material from the surrounding
landscape, collecting even more food and garden waste, and sourcing manure and straw from
local farmers.
But every year I have struggled to produce enough compost, partially due to effort it
takes to deal with bulk material like this, the fact that I need to proactively acquire
more materials well in advance of needing it, and the fact that the decomposition process
can take some time.
And this year, for the first time, I bought in a load of finished compost for the gardens.
With all of the different family scale growing spaces that I manage, I need a lot of compost.
Each season I use up to 3m2 of finished compost to amend the beds in the 100m2 Intensive Garden,
which is equivalent about 4 cubic yards or 30 full wheelbarrow loads of compost.
I also use about the same amount of compost for the Polytunnel Garden, which is the same
size and also following an intensive method.
I need at least 1m3 of compost for the Extensive Garden, and should really be using at least
2m3 for the Polyculture Garden.
The Simple Garden relies on sheet composting on the garden bed itself, rather than adding
finished compost, but still requires a lot of un-decomposed material.
And since I have changed to the method of using a thick layer of finished compost as
a surface mulch in my No-Dig Garden, this one growing space can easily use 5m3 of compost
each season.
So this means that I would need up to 14m3 of finished compost every year to trial all
these different gardening methods.
And that doesn’t include the amount of un-decomposed material that I'd need for the Simple Garden,
or any compost I might use in any other growing spaces that I have, or anything for the much
larger Black Plot.
But in recent years I have typically made between 6 and 8m3 of compost each season,
which obviously isn’t enough.
And last year I produced even less, mainly due to the really dry conditions which restricted
the growth in a lot of the landscape that I usually rely on for composting material.
So that means that I was really short of compost at the beginning of this growing season.
Over the past few seasons I've been searching for other sources of compost, but it's not
so easy in my context.
Many of the farmers around here use a slurry tank to manage the wastes from their animals,
which means that very few of them have any manure available.
I have manage to get in two loads of farmyard manure but it wasn’t mature enough for use
this season, and hopefully I'll be able to get some more in the future.
But I am hesitant to bring in non-organic manure supplies due to problems of herbicide
contamination that we've had in the area in the past.
And my friends with the organic farm really should be keeping all of their manure for
their own operations.
Thankfully, lots of people in the area have horses, and last year a friend and I borrowed
a trailer and hauled in a lot of partially decomposed horse manure from a small local
stable.
This was used primarily as a mulch in the No-Dig Garden, but unfortunately I wasn’t
able to do it again this season.
It is a lot of work to manage this bulk material, and I usually need to keep it and store it
for a while so that it can adequately decompose before I use it on the gardens.
This means that I have to acquire it before I actually need it, which is not something
that I’ve been good at in the past.
At the start of this season, I realised that I had less than half of the compost that I
would want for my gardens, and some of what I had wasn’t ready to be used yet.
So for the first time I decided to buy in finished compost for use in my gardens.
There are a couple of suppliers of compost here in Ireland, but it is a fairly new industry,
and there is not a lot of options to choose from.
I found a local distributor of supplies from one company that produces compost from garden
cuttings and other green wastes, and it's apparently certified as meeting organic standards.
It cost €55 per cubic meter bag, including delivery to my site, and I ended up getting
6 of these cubic meter bags delivered, most of which will be used for mulching the No-Dig
Garden.
I anticipated that the compost would not be of great quality, or at least not very rich
or fertile, but it was supposed to be free of viable weed seeds and disease organisms,
which was a good thing.
As most of this material was to be used as a mulch to cover surface of the No-Dig Garden
beds, I figured that the low fertility would not be such a big issue.
But I decided that I should probably add some chicken manure pellets, or some other fertiliser
that was high in nitrogen, in order to boost the fertility available to the plants wherever
I used this compost.
There is another supplier here in Ireland, that has been recommended to me, that apparently
produces compost which is much more suitable for vegetable growing, but that option is
more than double the price.
It really was convenient having a sufficient supply of finished compost available for use
when I needed it, even if the quality wasn’t great.
This material was easy to manage, and it really reduced the workload at a busy time of the
year.
It was also a nice change from my usual struggles of trying to figure out how to ration the
limited supplies of compost among all the different gardens that I was growing in.
It also meant that the compost that I did have was able to mature a little bit longer
which will make it more valuable later in the year and next season.
So far I have used about 4.5m3 or 45 wheelbarrow loads of this compost on the No-Dig Garden,
which allowed me to create a mulch about 50mm or 2 inches thick over all of the growing
beds.
I have also used almost 1.5m3 or close to 15 wheelbarrow loads of compost to dig into
some of the double dug beds of the Intensive Garden.
This finished off most of the 6 bags that I had bought in, and I ended up ordering in
another 2m3 of the same compost.
I've been using this supply to top up the beds in the Polytunnel Garden, either as a
side dressing or when preparing beds for the next crops, and occasionally I’ve used some
of it in the other gardens.
I still have one large bag of compost left and I anticipate that most of this will be
used to top up the mulch in the No-Dig garden as I plant late summer and the autumn crops.
This was a experiment for me, of making the most of what was readily available in my context.
And while this compost that I bought in filled a huge hole in my supplies, I'm not overly
happy about spending money on bulk soil amendment like this, and so far I am not really impressed
with the level of fertility that it had.
There are signs of possible nitrogen deficiencies showing on the potatoes and some of the other
crops in the No-Dig Garden, despite the huge amount of compost that I had applied.
And this was even after I had spread some chicken manure pellets in anticipation of
this possible deficiency.
On the basis of this it seems that it’s worthwhile to spend extra money on better
quality compost, and this is something that I need to take into consideration in the future.
I am planning to try compost from different suppliers, to better understand the balance
between cost and quality.
There seems to be a definite trend towards using gardening and growing methods that require
a lot more compost, such as variations on this No-Dig method.
No doubt companies and organisations throughout the country will respond to this demand, and
other sources will become available.
I think it would be really interesting to explore the possibilities of establishing
a composting facility that can operate at a large enough scale to produce all of the
compost that we would need in our community, but that’s a project for another day.
Growing vegetables is a resource intensive process and many of us struggle with not enough
compost of other forms of fertility.
With all of the growing spaces that I’m managing this year, and with the additional
spaces I’m planning to use next year, I could easily make use of 20m3 of compost a
season, if not more, and that's a lot of compost to produce.
In doing this I need to find a balance between putting in all the work to produce as much
as I can myself, importing bulk material for composting, versus buying in finished compost.
It makes sense to continue to develop and manage resources in my immediate landscape,
and to adapt the methods I use in my growing spaces to make the most of the resources that
are available in my context.
But if I'm going to continue to explore this No-Dig method or other methods that rely on
lots of compost, and to grow vegetables over such a large area, then I'm probably going
to need to continue to buy in compost.
I'd prefer to be more self reliant, but it is good to be able to source alternatives
that make things a lot easier, more productive and more convenient, even if they're not ideal.