
Fruit Trenches: Cultivating Subtropical Plants in Freezing Temperatures - Luc
https://www.lowtechmagazine.com/2020/04/fruit-trenches-cultivating-subtropical-plants-in-freezing-temperatures.html
======
hirundo
"Training small citrus plants was key to extending their cultivation across
all regions of the Black Sea coast, where until then it had been impossible.
This was achieved by pruning and guiding citrus plants into a creeping form,
which reduced their height to a mere 25 cm."

People complain about cubicle farms, but there's so much we can do to train
workers to be productive in them, if we start them young enough.

~~~
hyperpallium
> pruning

Do IT workers _really_ need legs?

~~~
hutzlibu
Of course not, if you can automate feeding. Sadly the current armless
interfaces are not efficient enough, otherwise there is a big potential there
as well. But the bonsai approach if applied young enough, should give
efficiency boosts, too.

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artificialLimbs
Super awesome! I imagine that most of the time, you don't even need to dig
giant trenches, though. Sepp Holzer grows citrus in the freezing alps above
ground. Their average temp is 5C.

[https://www.youtube.com/watch?v=5GMXqgQIU9c](https://www.youtube.com/watch?v=5GMXqgQIU9c)

~~~
VBprogrammer
Sepp Holzer's farm is amazing. I think however it's unlikely that he's truly
able to grow citrus fruit at scale even using all of his near magical
techniques. Where he is able to grow citrus fruit is taking advantage of very
small micro climates with ponds buffering temperatures and acting to reflect
evening sun along with perfect orientation etc.

~~~
hutzlibu
Permaculture in general sadly does not produce at scale at all and scaling up
is very labour intensive.

~~~
floatrock
The average car in the US has a 120 horsepower engine, less if it's a compact,
more if it's a truck or SUV.

Think about that for a second -- your garage is housing the equivalent of 120
horses. How much "labor" is that?

Now, we don't really notice that when everything is working well and the
gasoline keeps flowing. There are calculations that figure a gallon of oil has
something like two weeks of 8-hour/day manual labor embedded in it, energy-
wise (using the cute term "energy slaves"). Synthentic fertilizer is basically
spending a crap-ton of energy to fix nitrogen -- google "haber bosch energy".

Especially with the covid supply chain disruptions going on now, though, I've
been rethinking what "scale" means or if it's even the right metric to be
going for. Permaculture has been really interesting to me last few weeks
because it doesn't try to go for "scale" per se (though there are claims that
properly done it's _more_ productive per acre), but rather it tries to cycle
as many energy flows as possible.

So if your yardstick is "how many bushels of corn per acre can I grow?" then
yeah, permaculture doesn't 'scale'. But if your yardstick is "how do I get the
most output while minimizing energy inputs" and accept that outputs aren't
necessarily a monocrop but can be complementary outputs (corn + legumes +
animals + fertilizer), then it starts to get really interesting.

I'm a developer not a farmer, but the systems-level thinking I've seen in the
permaculture community is extremely fascinating. There's 'labor' embedded
everywhere, the question is are you counting it.

~~~
VBprogrammer
Not sure if you've come come across it but Gabe Brown has done some
interesting stuff in farm scale low input farming.

[https://youtu.be/uUmIdq0D6-A](https://youtu.be/uUmIdq0D6-A)

That said, I think there is a lot of interesting stuff in permaculture design.
But in a lot of cases it is a bit of a pyramid scheme / agile consultancy feel
going on.

~~~
hutzlibu
"But in a lot of cases it is a bit of a pyramid scheme / agile consultancy
feel going on."

Definitely, Sepp Holzer is sadly a prominent example of this as well. There
was a case of a new project, where a naive women, a true believer of
permaculture, invested all her money in a permaculture school project under
the guidance of Holzer, where all the ordinary farmers could learn how much
more efficient permaculture is. And it failed spectacular and ended in court.
[german wikipedia for more, english version is very small]

------
dharma1
I grow a few things in a (relatively small) suburban garden in London. My
experience so far with fruit normally associated with warmer climates:

Grapes - grow very well outside, lots of tasty fruit, sensitive to mildew

Figs - grow well outside, fast, but not much fruit yet

Citrus (lemon, lime and kafir lime) - Any frost is damaging, can only grow in
pots and bring in during winter. Grows slowly and doesn't produce much fruit

Olives - grow very well outside, don't produce much fruit

Stauntonia - grow very well outside, no fruit so far

Hardy kiwi - grows well outside, produces some fruit

Normal kiwi - grow very slowly, no fruit, sensitive to frost

I would like to try pomegranates, I've seen some people grow them in London

The best croppers in my garden by far are non-tropical fruit - cherry and
apple trees.

I think polytunnels (maybe with some kind of light transmitting insulation)
and geothermal heating would be the way to go these days in northern climates
if trying to grow cold sensitive fruit in larger amounts.

~~~
tathougies
The Europeans also used 'fruit walls'. I'm thinking of setting up one in
Portland. Basically a brick wall that you espalier a fruit tree to. You
redirect your chimney floo or hot water pipes through the wall to keep it
warmer than the surroundings in the winter. I'm hoping to be able to grow
frost-sensitive hardy citrus.

[https://www.lowtechmagazine.com/2015/12/fruit-walls-urban-
fa...](https://www.lowtechmagazine.com/2015/12/fruit-walls-urban-farming.html)

~~~
koheripbal
The problem is that neither your chimney nor hot water pipes are continually
piping heat. So the transient effect of the warm/cold cycles would likely make
frostbite even worse.

...and leaving those heat sources on continually... well... that's very energy
inefficient, to say the least.

~~~
floatrock
Idea behind the brick is to add thermal mass -- it stays hot once it gets hot
in the same way a freight train stays in motion once it gets going.

This is often done on north-facing walls in greenhouses. In winter when the
sun is low, the thermal mass gets a lot of light and absorbs it as heat. Then
at night it releases it to balance out nighttime lows. In summer when the sun
is high up, because it's a wall there's less surface area that absorbs the
radiation, so it's self-regulating to a degree.

Same idea is even used for _seasonal_ thermal storage. Look up "earth
batteries" on youtube, usually it's permaculture folks. Basically, put air
circulation pipes a couple feet below a greenhouse. In the summer, you flush
your (too hot) hot air through it, the ground absorbs the heat, and you cool
off your greenhouse. In the winter, the same process absorbs some of the heat
out of the ground. Some numbers I've heard is a greenhouse can stay at 50
degrees when it's -20 outside. Basically same idea as a geothermal heat pump,
but much simpler because all you need is a blower fan and some pvc.

~~~
netjiro
> all you need is a blower fan and some pvc

And a lot of land area.

That last part tends to be the problem.

------
scottlocklin
There was a similar article shared here a few months ago on Fruit Walls:

[https://www.lowtechmagazine.com/2015/12/fruit-walls-urban-
fa...](https://www.lowtechmagazine.com/2015/12/fruit-walls-urban-farming.html)

~~~
cardamomo
The fruit walls article a perennial favorite on HN.[0] (Pun intended.)

[0]
[https://hn.algolia.com/?q=fruit+walls](https://hn.algolia.com/?q=fruit+walls)

------
James_Henry
The soviet's probably would have liked this man's geothermal greenhouse which
is a modern version of their trenches:
[https://www.youtube.com/watch?v=IZghkt5m1uY](https://www.youtube.com/watch?v=IZghkt5m1uY)

Also, I'm wondering if the citrus grown in Russia ended up ripening in fall
rather than in winter or whether they had to harvest the fruit in the middle
of the winter. Also, I'm not sure how citrus would work being dug up every
winter. Did these trees ripen in the spring? This is all fascinating and
something I'd love to try in the US. I'd bet the premium on locally grown
foods isn't enough to sustain a northern citrus farm, but it could be a good
hobby.

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sunsure
This retire engineer in Nebraska has nice setup.

[https://www.youtube.com/watch?v=4O3ifR-3zvs](https://www.youtube.com/watch?v=4O3ifR-3zvs)

~~~
goda90
I wonder if these kinds of designs can handle smaller scales. I'd love to have
such a greenhouse on my 0.3 acre lot in Wisconsin.

Edit: I found this guy's store page[0]. This is what they say about size:
"Greenhouse in the Snow kits are priced by the lineal foot and are available
in 6' increments beginning at 30'. The greenhouses are 17' wide. Most kits we
sell are 78' to 102' long. Greenhouses less than 60' long are less cost
effective than bigger greenhouses."

I imagine smaller greenhouses like this are still possible though.

[0][https://greenhouseinthesnow.com/shop](https://greenhouseinthesnow.com/shop)

~~~
saltcured
Bear in mind that the ratio of the exterior surface to the volume of the
controlled space gets worse and worse as you make it smaller. And that this
ratio is what helps make it cost effective not just in material costs but in
operating costs, since heat transfer is across that surface...

------
georgeoliver
Where I grew up (41.3 deg N, on the Atlantic coast) I was always amazed by our
neighbor, who would bury his ~15 foot tall fig tree every year to protect it
from freezing. For some reason in my child mind it seemed to defy the laws of
nature, though of course it was quite the opposite!

~~~
DeathArrow
Where I live in Eastern Europe (44°26′7″), we have acclimatized fig trees. And
we have temperatures as low as -20C or even -25C (-4 and -13 Fahrenheit).

~~~
georgeoliver
My parents who still live in the same house do have a small fig tree they
don't bury, and my mother's parents a hundred miles south had a larger one in
their backyard. I don't know if burying fig trees in that climate is necessary
to be honest, maybe it was just a practice my neighbor brought with him (he
was Italian as well).

------
gdubs
Wow, this is amazing. The trenches are super cool, but there’s a wealth of
info in the article, especially around how they arrived at creeping varieties,
and how they cold-hardened lemons by painstakingly moving each successive
generation’s seeds further and further north. Really interesting piece.

~~~
chris1993
Very interesting reliance on epigenetics to get cold adapted varieties

------
derefr
I’ve often thought about the fact that most food into places like Barrow,
Alaska is flown in, and wondered whether it would be practical to set up local
infrastructure like this to grow food locally (with “practical” meaning “the
CapEx of doing so would be repaid in logistical OpEx saved over a small number
of years.”)

~~~
Spooky23
Forget about Point Barrow. I live in Upstate NY, one of the best Apple growing
regions in the world. I’m eating an Apple grown in Chile while local orchards
collapse.

Food has more to do with capital and commerce than anything else. The
inefficiencies of consolidated global scale distribution require squeezing
every penny on the production side.

~~~
samatman
It's not a requirement, it's a choice, and one with catastrophic downside
risk.

Refusing protectionist trade policy became popular among the people who make
these decisions, a trend which accelerated after the collapse of the Soviet
Union. We're in the middle of a crisis which brought to stark light the lack
of resilience created by this relentless focus on efficiency and productivity
at any cost.

But this is policy, not immutable law. Markets do predictable things in the
absence of trade protection, subsidy, and state investment, true; but they do
predictable things in the presence of them also.

~~~
Spooky23
I’m not talking trade policy. It makes sense to get summer crops from South
America in winter/spring! It ridiculous to get months old apples from there.
The US regulatory and monetary system facilitates big players.

Today you have buyer cartels purchasing in bulk and fixing prices. They demand
quantities and pricing that shut the market to most players.

I can’t buy lettuce in NY at retail because the supply chain from Arizona and
California is fubar. Farmers in NY will be harvesting lettuce from high
tunnels soon, but they don’t have access to markets and can’t scale.

~~~
dsparkman
The apple is not months old, but more likely a year old. They are kept in cold
storage for extended periods of time.

The truth is that it makes horrible sense to ship crops to the US from
anywhere outside of the US.

US agriculture policy is broken fundamentally. It is corn, soy, wheat. It is
what is used as the feed stock for industrial food production. Basically, all
the pseudo-food that lines your grocery store shelves. In the US, your tax
dollars are used to subsidize the production of this "food" so that it is
artificially cheap.

------
PcMojo
[video] Nebraska retired mailman uses low cost geothermal to grow citrus in
-20F snowy weather --
[https://www.youtube.com/watch?v=ZD_3_gsgsnk](https://www.youtube.com/watch?v=ZD_3_gsgsnk)

------
edaemon
The University of Minnesota has done a bit of research and put out some
guidance on constructing deep winter greenhouses:
[https://extension.umn.edu/growing-systems/deep-winter-
greenh...](https://extension.umn.edu/growing-systems/deep-winter-greenhouses)

They use a similar method in that thermal mass is used to store energy, but
instead of trapping the heat with soil/straw for a season the daily heat is
stored in masonry, stone, or water. On sunny winter days it can be -20°F
outside while the greenhouse is 80°F, though a string of dark days can mean
that supplemental heating is needed.

------
loeg
Some of these techniques are still common to produce hardy plants or increase
yields with low land use. "Creeping" is also called low-stress training, and
the extreme form is sometimes colloquially called "screen of green." SoG is
so-called because you essentially put a net at a fixed height and force the
plants leaves to all be at that exact height, attempting to maximize
photosynthesis efficiency. (Really hot peppers varieties take some babying to
thrive. These techniques are also popular in the marijuana community.)

------
kleton
It frosted only one or two days this winter in Odessa. So maybe in a few
years, you will be able to grow mandarins above ground without protection.

------
aaron695
Fruit Trenches are just an attempt at cheap walls. There is no geothermal
going on here.

I'm not sure if it would work out cheaper. Certainly not for a business. But
even for a hobbyist possibly not. I'm not sure it's even interesting as a
display garden.

The bio-hacking (breeding) of plants is cool though.

------
mooreds
An alternative is greenhouses. These folks have been growing tropical plants
at 7200 feet in the Rocky mountains for years using inflatable greenhouses:
[https://crmpi.org/](https://crmpi.org/)

------
jungletime
The most hardy citrus is the ornamental Flying Dragon Citrus, which produces
fruit, but the fruit is poor tasting. But can be grown in zone 6 Niagara Falls

[http://www.eattheweeds.com/hardy-orange/](http://www.eattheweeds.com/hardy-
orange/)

[https://en.wikipedia.org/wiki/Cold-
hardy_citrus](https://en.wikipedia.org/wiki/Cold-hardy_citrus)

The most tropical fruit that can be grown in cold climates in North America is
the Paw Paw. (Survives -30 degrees)

"It belongs to the genus Asimina in the same plant family (the Annonaceae) as
the custard-apple, cherimoya, sweetsop, ylang-ylang and soursop."

~~~
pvaldes
Flying dragon or Poncirus is a must if you want to grow Citrus in cold places.
Is the only decicuous Citrus.

The fruits are non culinary, but is an excelent rootstock

In any case the "lemon" of cold places is Chaenomeles (and not all are able to
bear fruit).

------
scrumbledober
I oddly really want to do this, but I live in California so that would be
quite pointless and most likely detrimental.

~~~
205guy
The Forestiere Underground Gardens in Frenso are over 100 years old. The trees
grow in wells connected by shallow tunnels. It does look more like a Tatooine
underground house than a garden, but still neat. It's open for tours in normal
times:

[http://www.undergroundgardens.com/](http://www.undergroundgardens.com/)

------
legulere
Reminds me a bit of the citrus gardens in Limone sul Garda.

[https://en.wikipedia.org/wiki/Limone_sul_Garda](https://en.wikipedia.org/wiki/Limone_sul_Garda)

------
datnoblesavage
I wonder if hackernews mods keep tabs on people carpet downvoting?

~~~
nkurz
They do, and are usually pretty responsive to questions like this if you send
them email at hn@ycombinator.com. I don't know if that's what's happening
here, though.

For example, despite having a copy of one of Holzer's books next to my bed, I
downvoted your "Sepp [heart]" comment. It's just not the right comment for HN:
no context, and emoticons are really frowned on. If instead you'd written a
few sentences explaining why you admire him, so that people who don't know who
he is could understand, you'd probably have gotten a bunch of upvotes.

I'm sorry if it feels like people are attacking you. It's really not, instead
it's really about trying to keep the site as good as it currently is. Almost
all comment heavy sites of this age have declined to be unusable by now, but
because of the different moderation approach, HN manages to (at least
occasionally) still have quality discussion.

------
paypalcust83
Climate-controlled cultivation will likely become a necessity for food
production as climate change intensifies. Spain, South Africa, many Middle
Eastern and other countries are already heavily reliant on greenhouses.

Also given that megadroughts, floods, and hurricanes are likely to be the new
normal, sufficient capacities of solar-powered desalination will be important
to sustain food production levels. My main immediate concern with climate
change is that greater numbers of and more intense storms will destroy
infrastructure and food production, leading to wars and/or pan migration.

~~~
Scoundreller
Problem is that greenhouses are the most laborious. Can’t drive a tractor
through to plant and pick everything.

~~~
glaberficken
Actually its the other way around! Automation in the controlled environment of
a greenhouse is much simpler to implement than out on a field. Ok, there are
certain crops that still haven't been cracked in terms of automating the
picking mostly due to fragility/spoilage of the items being picked, but other
than that, you have a regulated climate/humidity/temp (you can pause "rain" ,
etc in sync with the tasks you want to automate), you have a flat surface for
your machines, or vertical rigging to hang machines off of, etc.

~~~
mod
Sure, but one guy with a tractor in a field has a lot of advantages over that.

------
datnoblesavage
Thanks for the heads up. Have you got the printed books version? If so, are
they good?

------
mrfusion
If the temps are below 0f, it seems like none of this is preventing your free
from dropping below freezing. Maybe it’s really more about the varieties they
cultivated.

With modern crisper I bet you could Make some amazing frui trees.

~~~
netjiro
Join together with some fellow biohackers and make a fun transgenic plant.
It's not that expensive or difficult, if you choose the plant well. Then
you're a proud God of GMO with your intellectual spawn multiplying to
(probably not) conquer the earth...

But some plants are very tricky and costly.

I remember making my first transgenetic GMO in an afternoon back in the day.

