I started the Simple Garden 5 years ago as an attempt to be able to grow a lot of food, without
having to put in a lot of time, and accepting that I was going to have to give up a fair
amount of choice and diversity in the process. It is essentially a simple crop rotation, and
soil fertility management method that focusses on growing four different staple crops for storage,
to provide us with lots to eat in the autumn, through the winter, and into the spring.
And for each of the past five seasons I have been growing the
same four crops with essentially the same techniques, with occasional adjustments,
and I think the garden has been quite successful overall.
But with fewer crops it means that any issues that arise with one of them will have a larger
effects on the overall yield of the garden. And the four crops that I have chosen can
be tricky enough to grow despite 3 of them being very common crops here in Ireland.
In some significant ways this garden is improving each year,
with some key setbacks and unexpected successes, all of which raise some interesting questions.
Perhaps the most unusual part of this garden is the use of sheet composting over one third
of the soil area underneath the squash plants in one of the three crop rotations.
I have used a wide range of different materials for this sheet composting,
and for the last year I relied primarily on hay and other
organic material from clearing overgrown sections of the surrounding landscape.
This rough material was topped up with lots of nettles, comfrey leaves and grass
clippings from the fresh growth of the spring. And the squash plants grew quite strongly,
and seemed more vigorous than the same plants in two of the other gardens.
We were able to harvest 140kg (308lbs) of squash from the 9 plants in this patch, which was a bit
less than the previous two years, and the average weight of each squash has been fairly consistent
over the years at around 4kg each (8.8lbs), which is what I would expect from a hybrid variety.
Comparing all of the crops of this same squash variety that have been grown in
the outside gardens over the past five years, the yield and average size is slightly lower
in this garden, but within the same range. But the consistently larger number of squash
produced per plant in this Simple Garden over the 5 years is quite striking, and I wonder if this
is due to the sheet composting, which is one of the key differences between this and the gardens.
Because I have used significantly different material each season for this sheet composting,
I don’t think this difference is due to the balance of nutrients that would be supplied,
but more because the decomposition is taking place directly over the roots of the squash plants.
It is possible that this decomposition is providing a little bit more warmth for the soil,
and sheltering it from the cooling influence of the wind, and insulating
the soil from cooling down in the autumn. All of this would possibly benefit these heat
loving plants, but the covering would also prevent the sun from warming up the soil in the spring.
Whatever the reason, this crop grew quite well, though it was a bit more delayed in maturing,
which might explain some of the lower yields, but I was concerned that some
of the squash would not fully ripen. But we have been pleasantly surprised
by the excellent quality of at least some of the squash from this garden,
which has had very full flavour and was quite sweet.
A few of them were possibly the best tasting squash we have ever produced,
or at least they are better tasting than what I ever though would be possible to produce in
this maritime climate here in Ireland, and I don’t really know why they were so successful.
The simple crop rotation plan that I follow for this garden has potatoes being grown in the bed
after the squash, which starts with raking off of the remains of compost from the year before,
and digging over the soil for the potatoes. I have been adding chicken manure pellets to
the trenches created for the four rows of potatoes, as I wasn’t sure if there
would be enough fertility leftover in the soil from the sheet composting the previous year.
This is the only garden that I have grown main crop potatoes, and I grew 4
different varieties (list varieties) last year that I don’t have a lot of experience with,
so I can’t really compare how well they did. I don’t think fertility was a limiting issue
here and I wonder how much the yield might have dropped if I hadn’t topped
up the fertility at the beginning of the season. After the digging out the potatoes each autumn,
we have been preparing and covering two beds for the onions and main crop carrots to be
planted in the following spring, combining to form the third year of the rotation plan.
And last year we didn’t add any additional fertility or compost to this soil for the carrots
and onions, so the crops were still relying on what was leftover from the sheet composting
and the chicken manure pellets after the two heavy feeding crops of squash and potatoes.
The crop of onions last year was great, the best crop yet out of this garden despite some issues,
and there has been a continual increase in yield over the last few years.
So I don’t think lack of fertility has been an issue.
But the carrot crop was quite poor last year, with a yield only a bit better than the previous year,
which was itself a dramatic decline from the very first season which was one of
the best carrot crops I had ever produced. I don’t think the poor results this year were
a fertility issue, and was more related to poor germination, some pest damage,
and excessive amount of forking of the roots. I still don’t know why there has been so much
forking of the carrots in the past few years, and I wonder if it is because of
how and when the soil was cultivated, or if it’s some other factor I am not aware of.
There were also pest issues with the carrots, including slugs killing off the young seedlings,
which probably caused the biggest reduction of yield this past year.
We were also not so successful at keeping out the carrot root fly last year,
probably because we didn’t have the cover the crops early enough, and the burrowing larvae
added to the forking of the roots to further reduce the useable portion of this crop.
There are of course ways to deal with these pests, but we didn’t
use them early enough or consistently enough to be able to prevent damage,
and with the crop of onions, we didn’t keep the protective measures in place for long enough.
The numerous jackdaws and rooks in the area seem to enjoy pulling the onion sets out of the ground,
probably in search of worms around the developing roots,
so we usually cover the beds with netting or some other covering, held off the ground with hoops.
But last year we removed the netting too early, thinking that the plants were large enough,
and quite a few of the young plants were pulled out of the ground,
or had their leaves snapped off in the attempt. About 20% of the plants in this large crop were
damaged before we put the netting back on, and the great yield of onions from
last year would have been even better if we had just waited a little longer.
With the potato crop, we probably waited too long to harvest, and a considerable
number of the tubers were damaged by slugs. This is a fairly usual occurrence in these
gardens, and seems to be caused by a species of slug that spends most of its time underground,
and therefore seems to be able to escape our usual slug control methods.
So I think harvesting earlier is probably the best option for reducing damage,
and is probably the better option with the carrot crop as well.
In the past the crop of onions were badly affected by downy mildew,
compounded by the wet weather that we often seem to get as the bulbs were maturing.
Harvesting the plants earlier would have been one way to deal with this,
even though it would reduce the yield. But in the past two years we have been using
sets from different varieties of onions which are apparently resistant to downy mildew,
and we have seen definite improvements, especially this year.
And this change of varieties is likely the main reason for the improved yields.
With the 4 varieties of potatoes that we planted this year, one was not very productive and I
suspect it is just an unsuitable variety. Another variety had an equally low yield,
but this was because blight affected the leaves quite badly,
and we cut down all of the stems to prevent the blight spreading or affecting the buried tubers.
The other two varieties are definitely worth growing again, though one of them seemed to
die back early and the other seemed to keep growing for quite a bit longer,
unaffected by blight or other diseases.
So growing the right variety is a good way to improve the overall yield of potatoes,
and if we had grown only the two more productive varieties, then we could have harvested an extra
50kg, or 25% more from this patch last year. And it is possible that other varieties would
do even better, and it is good to have a few different types to eat,
so this year we are trying another two in addition to the successful ones from last year.
With the carrot crop last year, we grew 5 different varieties, and some seemed to do better
than others, but I would be hesitant to select any because of the other issues that we had.
So we are planning to grow a range of different main crop varieties of carrots again this year,
hoping to find ones that grow well ad taste great, so that we can get back to
the possibility of growing an abundant and flavourful crop of this important vegetable.
With the squash crop I think we might stick with the same variety, to see how it goes
next season again, and we could do the same thing with the onion crop, buying in another
batch of sets for the same successful variety. Although the crop was really good last year,
we still had quite a few of the onions decay or rot in storage,
which apparently can be more common with you are growing from sets rather than from seeds.
So we are going to try to grow the onion crop from seed this season in this garden,
and as I don’t know what variety would be best, we are going to take the opportunity of doing
a broad variety trial, to get a better sense of the range and possibilities of using seeds.
This will no doubt take more time, and the yield will likely be a lot less next year
as some of the varieties just won’t grow well at all.
But we are hoping to find a few varieties that will be as productive and disease
free as our crop was last year, but with better storage possibilities.
One of the key benefits of this garden has been less weeding,
partially because the squash bed is covered, and the potato plants can outcompete the weeds,
leaving only the onion and carrot patches to weed. And we have been covering this entire garden
with ground cover fabric over winter, which suppresses existing weeds, and prevents more
pernicious weeds from becoming established. This definitely reduces the amount of time
spent weeding but it does require all that material, and the effort it takes to keep
it secure and adequately weighed down so that it doesn’t blow away in the wind.
There are also definite benefits in protecting the soil from the heavy rains of the winter,
and it is really easy it is to sow crops into a clean and prepared beds,
but I do wonder how well this garden would work without these big sheets of plastic.
The recent shift to using rough grasses and other biomass from the surrounding landscape
as sheet composting to cover the squash patch,
means that this plastic fabric is not as necessary for part of the garden at least.
And while it is useful to have a place to put all this overgrown rough material that
I collect from around the area, it does come at the risk of bringing additional
seeds from the grasses and other plants. And I wonder if several years of this
approach will significantly increase the store of viable weed seeds that are in the soil,
that we will only end up having to weed out of the carrot and onion patch.
Overall, I think this has become quite a successful garden, as it produces
a lot of food with considerably less work than the other gardens.
The overall yield last season was a bit lower than in previous years, but still more than half a ton
of food produced in the 100m2 area, with a total of about 30 hours spent working in this garden.
This translates to about 17 kilograms of vegetables to put into storage
for every hour that we worked throughout the full year in this garden, though probably a bit less if
we discard some of the more pest damaged crops. That is considerably more than any of the other
gardens we manage, which would usually be in the range of 5 to 7 kg per hour,
though we do get a lot more choice. And there is always room for improvement, and
quite a few questions that I would be interested in exploring, in order to improve the quality,
resilience and productivity of this garden. Such as, why do the squash plants produce
more fruit in this garden, and is the sheet composting involved?
Can the fertility be improved, or what would happen if the concentrated fertility wasn’t added?
Are the carrots forking because of how and when the soil is cultivated, and if it isn’t that,
what is causing so much forking of these roots? Can pest damage be radically reduced by
focusing on better timing of control measures and timing of harvesting?
Will selecting appropriate varieties deal with all the disease issues?
How much can the yields increase if better varieties are grown?
Are onion seeds better than sets for growing in this garden?
What would change if the ground cover fabric was not used?
Will weed seeds build up in the soil if we
continue to use grasses and other rough material as sheet composting?
And, how much more can this garden produce with less time spent?
It is interesting that with so few crops and relatively simple methods,
there are still so many questions, and possibly many more.
I think part of this is because the 4 crops we are grown are not so easy to grow,
or have definite pest and disease issues. But, perhaps I am simply able to explore
all of this in more depth with this garden because there are so few crops, whereas in the
other gardens there is always so much more going on, that it is hard to focus in on the detail.
But, perhaps it only takes a closer look to discover many more questions.