Starting a vegetable garden or growing space always involves disrupting what is currently
on the ground and somehow transforming it into a productive space for vegetables.
This can be a relatively easy task, if you are starting with a flat lawn or a clean meadow
that has deep fertile soil, and is clear of debris and perennial weeds.
But in many cases, especially in an urban context, we're looking at an uneven site,
with difficult access, over gown with pernicious weeds, and aren’t entirely certain what
lies beneath the surface of the soil, or even hidden among the vegetation.
This is what I faced with a 150 square meter section of the Black Plot that I wanted to
establish as a growing space, which had been the site of a former polytunnel that had been
destroyed in a storm a number of years ago.
The site had been abandoned, leaving plastic from the edges of the polytunnels still buried
in the ground, and the site was very uneven with remnants of raised beds and piles of
soil, compost and stones.
In addition, the north end of this space was cleared to build the compost demonstration
facility, and all the topsoil and vegetation had been left in a large pile on part of the
space that I wanted to clear.
Over the last few years this area had been invaded by some fairly pernicious weeds including
scutch grass, creeping thistle, and a lot of nettles and other perennial weeds.
But the site has a lot of potential, and with all of the plans for the area, this site will
eventually become a sheltered high value growing space, which I see as a zone one or two within
my permaculture zoning for the site.
I planed to lay out the space in a series of fixed beds for high rotation crops, and
seed saving, variety trials, and a lot of other explorations.
But first I needed to figure out how to transform this really messy site into a clean and productive
growing space.
The use a broad spectrum herbicide to killing off the existing vegetation on this site was
not an option, and because of the constraints of the site and the uneven ground it would
have been difficult to get in a tractor to plow or till the soil, and I decided against
getting in a backhoe or digger to do the heavy work.
I felt that using a rototiller to do the job would be quite problematic, as the uneven
site and the buried plastic and stones would make it a really tough task, and I didn’t
want to chop up and distribute all of the scutch grass roots.
I had contemplated bringing in a few pigs for the summer, to get them to do their natural
thing and to till up all the soil, but I don’t think I’m ready for the additional tasks
and responsibilities of being a pig owner.
So it seemed that I was going to have to do most of the hard work myself, which I don’t
mind too much and have done a lot of it in the past.
The simplest way would be to methodically dig over the whole area, removing as much
of the weeds, plastic, debris and larger stones as I could in the process, which would have
involved a lot of bending to collect the material by hand.
I had used an adaptation of the lazy bed method to establish fixed beds in another larger
section of the Black Plot a few seasons ago, which involved cutting out clumps of sod and
turning them over to bury them under the growing bed.
This was a reasonable option in the flatter areas of the plot, but I don’t think it
would have be as successful in this rougher section of the site, and there had still be
a lot of work to get rid of the pernicious weeds in the following seasons.
I had also used a method of simply turning over clumps of sod, levelling the soil a bit,
and then covering the surface with a ground cover fabric, which had worked fairly well
in a really rough section that I had then planted with squash.
I had also used a variation of this method to establish my new polytunnel last year,
where I dug over the ground, leaving most of the weed roots in place, and then covered
the entire area with a ground cover fabric.
I then planted tomatoes, cucumbers and other larger plants in holes melted in the ground
cover fabric, which allowed me to get the space established quickly enough to get a
crop that summer.
I could've used some version of this ground cover fabric method, to get a crop of larger
plants in the first season, before establishing better growing beds for the following season,
if I was willing to wait another year.
As usual, I wish I had started this process a year or two ago, which would have definitely
reduced the workload this season and opened up a bunch of other options.
There are of course a number of no-dig approaches that I could use.
If I could get my hands on enough cardboard, straw, spoiled hay, and other materials, I
could have covered the entire site with a deep litter mulch, which would have killed
off all the weeds and boosted the soil life and fertility in the process.
But I've tried this method in other gardens, and have found it to be a bit problematic
in this cool and wet climate, especially as the slug population always dramatically increases,
making very hard to grow anything for at least a few seasons.
A better no-dig approach for this climate seems to be a method developed by Charles
Dowding, of covering the cardboard and paper with a thick layer of finished compost.
I calculated that I would have needed up to 12 cubic meters or about 15 yards of compost
to cover this entire 150 square meter site to a depth of 75 millimetres or 3 inches,
which is a huge amount of material, or about 120 wheelbarrows loads full, but I think is
a minimum I would need to do the job on this rough site.
If I had that much compost to spare, or could get enough of it locally, I'd consider using
this method, but I don’t, and clean good quality compost is hard to get around here,
especially at that volume.
Another option would be to use a substantial layer of wood chip as a covering, which is
often referred to as a back to eden method.
Wood chip is a bit easier to get than compost, and cheaper in this area, but I am not sure
if this type of wood chip mulch is compatible with the diversity of types of plants I want
to grow in this section, at least for the first couple of seasons, but I may wrong about that.
All of these no-dig methods would require a substantial amount of work bringing in and
spreading around a large volume of material, none of which I have ready access to, and
would probably need to pay for.
And none of these methods would necessarily resolve the issues of the uneven site and
the buried plastic, although I could dig out the plastic and level the site first, but
this seems to go against the principles of these methods, or I could work around and
adapt to these quirky site characteristics.
One possible option that I hadn’t thought of before would be to bring in loads of additional
topsoil, and just raise the entire section of the garden, burying everything including
weeds, stones, debris, plastic, and dramatically increasing the depth of topsoil in the process.
It would need to be quite a thick layer of additional soil in order to level the site,
and prevent the regrowth of the weeds, but if I did the work before hand to dig out some
of the higher sections of the ground, and dig out some of the plastic while I’m at
it, and then to put the soil on top of a layer of cardboard or paper, this would help to
dramatically reduce the amount of soil that is needed.
This is a resource that I do have access to for free, as we have a lot of topsoil on site,
left over from the development phase of the community, and it's located less than 100
meters away from this part of the plot.
It does have a fair amount of stones in it, as well as weed roots, and would take some
additional work to clean it up before I imported it into this part of the plot.
I'd need help of machinery to move that volume of soil, if I wasn’t up for hauling the
200 to 300 heavy wheelbarrow loads of soil that distance, but methodically digging out
and hauling 2 or 3 wheelbarrow loads of topsoil a day over the summer months would've done the job.
Because this resource is so close and available I wish I'd thought about using it before,
as I might have taken this option.
What I ended up doing is methodically digging and sifting the soil with the help of the
rugged compost sieve that I built and adapted.
It was a lot of work, but I spread the work out over a few months, and I think I'll end
up with the best results, with clean and prepared growing beds ready for next season.
First I used my scythe to cut down all vegetation, as close as I could to the ground, which I
removed for composting.
Then I set up a barrier around the site and i brought in a bunch of retired hens from
a small local egg supplier to help with the task.
Using my sharpened spade I cut sections of soil and weed roots, lifted them onto the
sieve and bashed them around a bit to loosen the soil from the roots.
I then manually pick out all the roots and any unwanted debris, and work the stones towards
the lower end of the sieve, and all the soil would fall through the holes in the sieve
to the hens waiting below.
Each day I would try to cut and sieve 1 or 2 square meters of ground, which would take
me about 15 or 20 minutes depending on the conditions of the soil in that location.
This would create a substantial pile of sifted soil which the hens would methodically dig
into looking for worms, grubs and seeds, which kept them quite happy and supplemented their
diet, and I got lots of eggs.
Every few days I would haul a wheelbarrow load of stones to areas where they were useful,
and I built up quite a pile of weed roots for hot composting.
This labour intensive process was doing a lot of jobs at once: I was able to really
loosen the soil, remove the vast majority of weeds, dig out clusters of larger stones,
remove a lot of the smaller stones, clear out all the buried plastic and debris, and
feed the hens.
What I ended up with is lots of loose, clean soil that is easy to move around and shape
into deep level growing beds, and the lack of stones will make cultivating and hoeing
this section of the gardens a lot easier for many years to come.
And as a bonus the full site is already well fertilised with lots of chicken manure.
It was a lot of work, possibly taking up to 40 hours in total, but this was spread out
over a couple of months.
It was a useful task to do and I learned a fair amount in the process.
It was interesting experimenting with changing the slope of the sieve and the particular
technique that worked best for the type of root systems that were in the area, or how
dry or wet the soil was, and I was surprised at how well it worked when the soil was quite wet.
I also found that the sieve could accommodate 3 or 4 people working at the same time, which
definitely sped up the process, especially when I was clearing the larger pile of soil.
The hens did help, although they were not a necessary part of the process, but the fact
that I was feeding them helped me keep at the task of doing it almost every day.
They did clear out a lot of the undesirable grubs and weed seed, but they also ate a lot
of the worms, many of which were probably already injured with my digging.
This process definitely disturbed the soil ecosystem, but once the fixed beds are made,
and the compost is added, and the paths are covered with wood chip, I plan to use minimal
surface cultivation or even a no-dig method into the future, and no doubt an abundant
and healthy soil ecosystem will develop again fairly quickly.
Some smaller pieces of scutch grass roots fell through the sieve, and I'll have to make
sure that they don’t become established again.
And of course there will be loads of weed seeds ready to sprout in the spring, but I
plan to burn them off with my flame weeder.
This option of using a sieve to clear rough ground to establish a garden isn’t perfect,
but it did a pretty good job in this context.
I've front loaded most of the work and all of the soil disruption, and this site will
be much more productive and easier to manage in the future.
I like to see it as a process of maximising effort, with the hope of maximising possible
benefit, and occasionally that’s the way I like to do things.