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TABLE OF CONTENTS

What is a Walipini Greenhouse? 3

The history of the Walipini pit 4

How does it work? 5

Why you should build your own Walipini 7

How to build a Walipini Greenhouse / Location 8

Size 10

Venting 11

Exterior Drainage Solutions 12

Interior Drainage Solutions / Costs 13

Costs 14

List of tools and materials 15

Building the Walipini / The Excavation 16

The Flooring / The Walls 17

The Roof 20

Completion 21

What can you grow in a Walipini? 22

Conclusion 27

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In recent years, more and more people have become aware of how

important it is to grow your own food and provide for your family by making the

most of your backyard space. With the advent of internet communication and

social media, innovational projects and techniques of small-scale agriculture have

made their way across the world, from one grower to another. The latest one to

stir the interest of dedicated gardeners comes from the South American

heartland and is called: Walipini.

A Walipini is an underground greenhouse that relies on the earth’s natural

temperature to create a suitable environment where plants can develop properly

regardless of the outside climate.

With a limited budget and a few spare weekends you can build your own

pit and never again be bothered with protecting your vegetables from hail storms,

drought or frost. I will present you with the plans to build a Walipini greenhouse

in the next chapters, but first let’s take a look at the technology behind this

gardening wonder and what makes it so efficient.

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It is hard to talk about a Walipini without being struck by its uncommon

name. If you are hinting at a Native American origin for it, then you guessed it

right. The term comes from the indigenous people of the Andes Mountains in

Bolivia and it stands for “place of warmth” in the local Aymara language. It seems

that entire communities across the Andes Mountains have been using the

Walipini pits for thousands of years to grow hardy crops and root vegetables in

areas where normal, aboveground agriculture was practically impossible due to

high winds and the extreme frosts of winter. There are even some accounts of

banana trees being grown at elevations as high as 14,000 feet in Walipini

greenhouses, but I am guessing that you are looking for more practical products

coming out of your greenhouse. The idea of going underground and

implementing the Walipini technique only hit the North American shores a

decade ago. However, many gardeners and preppers out there have chosen it to

develop a self-sufficiency method of agriculture that replaces the traditional glass-

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covered greenhouses and grow-holes topped with flimsy plastic coats. In recent

years, the Walipini has become a trademark of self-sufficiency and reliable

agriculture in many parts of the world, from the Mongolian steppes to the North

of Scotland and from the Australian coastline to the U.S. heartland.

The earth’s temperature levels tend to fluctuate between 50 and 60°F at

depths that range from 6 to 12 feet underground in different areas of our planet,

depending on latitude of course. This means that you can safely grow your

vegetables in a Walipini even during the harshest months of winter. Also, during

extreme heat conditions and dry summer spells, your plants will benefit from

cooler surroundings where they will be able to thrive naturally. In scientific terms,

the uniform layer of heat that we find in the first few feet underground is called

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the thermal constant, and it’s the natural fuel of the Walipini. The design of this

subterranean greenhouse is based on a rectangle shape dug 6-8 feet deep in the

ground. Its muddy walls act as a dense, natural material that gathers the heat

received from the sun during daytime and stores it for the night to prevent the

plants from experiencing sudden drops of temperature that would normally kill

them. The roof is most commonly provided by plastic sheets that allow a good

amount of natural light to be delivered to the inside plants.

The Walipini walls can be strengthened with anything from pine needles,

corn husks, wood beams, to brick tiles. Ventilation systems should be included to

allow for the temperatures to be controlled in warmer seasons. When considering

building a Walipini it is crucial to consider its placement. If improper water

drainage is not taken into account, water penetration of the walls can lead to

mold, damaging the crops.

Upon building the pit, you must make sure that its longest area faces the

South (in the Northern Hemisphere) and the North if you live below the Equator.

This will allow the construction to take advantage of as much sunlight as possible,

regardless of the season.

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Having a garden can be very cost-effective, especially during times of crisis

when weather conditions prevent large crops from developing and the grocery list

ends up to be too hefty for your wallet.

An underground greenhouse proves its worth even if the area that you live

in is not marred by storms, frosts or endless droughts. More than that, it is the

best way to make use of natural sources of energy and heat without having to

invest in a complex system that would normally keep you on the grid and at a

higher price.

Here are just a few other reasons why you should choose to build your very

own Walipini:

It is actually very affordable to construct.

It is easier than other greenhouse models to control the internal

temperature,

It can produce very large volumes of year-round food.

It provides the maximum benefit to financial and labor investment ratio.

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Initial considerations

Building your own Walipini is more than just a hole in the ground with a

plastic cover thrown over it. In order to complete this DIY project properly, there

are a few elements that you should take into account. It would be a good idea to

apply the following considerations to your own construction before heading to

the hardware store with just the list of necessary tools in your pocket.

1. Location

Carefully inspect the future building site of the Walipini. Make sure that

your backyard has all the necessary components required by the project.

Choosing the right location will eventually determine the success of your Walipini.

Beware of water penetration and the contents of the soil you want to dig

into. If water manages to seep through the walls, they will eventually collapse.

Should the water come up through the floor from underground sources, it will

have a destructive effect for the plant growth and it will even promote plant

disease.

Place the Walipini in an area where its foundation is at least 5’above the

water table. After you finish the above ground walls you should add a layer of

water-proof clay, such as or plastic sheeting. The latter should be buried

approximately 6” to 12’ under the berm surface. There are certain cases where

the soil has a low permeability rate. If you are lucky enough, the clay or plastic

may not be necessary. Do not forget to dig a shallow drainage ditch around the

perimeter of the Walipini. This adjacent construction should lead the drained

water far away enough from your pit, to prevent it from infiltrating back and

possibly flooding it.

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Build the Walipini in the direction of the sun’s transgression, which is in a

rectangular position, from east to the west and with a tilt angle of the roof that

should be facing the winter sun in the Southern Hemisphere, or pointed towards

the south if you live above the Equator. This will guarantee that your plants

receive a proper amount of natural light during winter. A longer exposure to the

sun will also allow the pit walls to store more energy and provide the crops with a

higher degree of temperature at night.

There is a very simple way to calculate the best angle of the roof to allow

maximum sun exposure at the winter solstice (the shortest day of the year), by

using the following rule:

a) Study a reliable map and find out the latitude on the globe. The Bolivian capital

city, La Paz is located at exactly 16.4º south of the equator.

b) Next, add approximately 23º which will make a tilt angle of 39 - 40º for the La

Paz region. This will actually place the direction of the roof perpendicular to the

sun during the winter solstice. This way, at that given time, your Walipini will

benefit from minimum reflection and maximum light penetration.

During the summer solstice this very angle will have the exact opposite

effect and maximize reflection while decreasing light penetration.

You can tweak this angle’s position, but this will change the original design

of increasing the heat during a winter solstice and reducing it at the time of the

summer solstice.

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2. Size

The standard recommended size for a Walipini structure is 8ft x 12ft.

However, you should consider the fact that a larger Walipini will provide you with

more produce for every per square foot. If you plan to sustain your family year-

round with this Walipini, keep in mind that you will need a minimum of 94 sq. ft.

of growing space per person.

Maintain the size of the Walipini easy to operate and maintain. Only this

way you will find that it is a cost-effective solution for the long term. Overbuilding

it might actually have a boomerang effect for your strategy and can even damage

the crops.

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3. Venting

Venting is an essential factor for your Walipini. You must make sure that

your underground greenhouse will not suffer from overheating or an excessive

level of humidity. If the pit will have too much venting, this will lead to crop

destruction, as it will happen if a high amount of humidity will dampen the

interior. Therefore, optimum balance must be kept to ensure proper plant

growth.

The original method used by the inventors of the Walipini is that of

ventilating with the help of two opposite doors placed at each end of the

construction. It is a cheap method that does not require any additional vents or

materials. However, it does not offer the possibility to manually adjust the level of

ventilation, which in some cases can prove to be crucial for the crops.

Another reliable method, of more recent innovation, uses the same doors

with the addition of a vent of equal size as one of the doors when the vent is fully

opened. You can place this vent at the top of the back wall. It is an essential

improvement to the previous method and it allows the Walipini to create a

natural circuit of the ventilated air.

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Nevertheless, this solution is not perfect. The heat storage mass is,

unfortunately, sent to the back wall where most of the heat is collected. By being

very close to the outside surface, which in most cases has a different

temperature, it could lead to the forming of condensation on the top ceiling. To

prevent this from happening, regular adjustments to the exterior back wall have

to be operated by contouring and sealing the berm at the vent on the exterior

back wall.

4. Exterior drainage solutions

The Walipini relies on water to function properly. However, water can also

prove to be its worst enemy if the drainage system is not constructed and

handled properly.

The exterior drainage of all the water resulted from rainfall is crucial for

your underground greenhouse.

Therefore, the berms must have sufficient incline away from the walls of

the construction to lead the water away quickly and effectively.

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If the soil at the base of your pit is extremely porous, you might have to place

a layer of clay or a layer of plastic sheeting from the rammed earth wall to the

perimeter drainage ditch. You must build the ditch as far away from the interior

wall of the building, depending on how efficient one can seal the berms and

transport the water away from the Walipini.

The recommended berm length for the back wall is of about 10ft. This will

prevent any moisture from clinging on the wall and it will inhibit water

penetration.

5. Interior drainage solutions

The main goal of the interior drainage system is to keep moisture from

building up at an excessive level that might lead to terminal damage for the plants

grown in your Walipini pit.

When you start digging for the construction, excavate at least two extra

feet from your initial calculations. This intermediary level will be filled with stone,

gravel and other filtrating material that will ensure the upper layers of soil from

becoming moldy. Place the larger stones at the bottom of the hole and then

gradually add gravel to top a portion of no more than two feet, before adding an

even layer of the excavated excess.

Should you find that your Walipini is holding in too much moisture, increase

the level of ventilation and even consider decreasing the amount and frequency

of irrigation.

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6. Costs

The Walipini is a DIY project and therefore, it should keep the construction

costs to a minimum. Before beginning to work on it, take into account these few,

cost-effective tips:

1) Free labor – Ask one or two friends to help you out with the hard, manual part

of the project.

2) Use all the amount of dirt that you excavate to strengthen the walls and avoid

paying for extra material.

3) Do not invest in unnecessary concrete footings and foundations! You will not

need them and you might even expose the pit to accidental flooding, as any

excess water will have no way to penetrate the bottom ground.

4) Chose plastic ultraviolet (UV) protective sheeting for the top and underside of

the roof. Stay away from glass or corrugated fiberglass

5) Go for 4” eucalyptus poles when choosing the materials needed for spanning

the roof.

6) If you do not have enough gravel, use the top soil from the dig for the bottom

planting soil.

7) Use the rest of the soil from the dig to boost the earth walls and berms.

8) When excavating, if you stumble upon any large stones, use them for the

drainage system.

Building a Walipini might have a different cost depending of the area you

live in. As a reference point, the materials used building a regular La Paz model

with only the traditional features (20ft x 74ft) are somewhere between $250 and

$300.

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7. List of tools and materials

We know that the initial design was suitable for people living in adverse

conditions and with a limited amount of tools at their disposal. Fortunately, you

will benefit from modern technology and the latest available tools to ease the

process of building your own Walipini.

Here is what you will need:

20pcs 4” x 16’ poles or PVC pipes used to span the roof

3pcs 3’ x 6’ hinged doors (one is for the 3’ x 5’ vent cover)

3pcs 3’ x 5’ door frames ( 2 if rear wall vent is not used)

2pcs 3’ x 6’ door lintels

1pcs 6’ x 3’ vent lintel or roof frame for vent, if used

1700 sq.’ of 200 micron agro film (polyethylene UV plastic) 640’ of 1” wood

stripping to secure plastic sheeting to the poles Shovels,

tractor or ox drawn plow to dig hole

30 cubic. Yds. of gravel for the floor drainage system

1 cubic yd. of gravel or stone to fill the 2 drain sumps

233 cubic yds. of soil will come from the excavation

22 cubic yds. of top soil for planting (8” x 66’ x 12’)

94 cubic yds. for the rammed earth walls

109 cubic yds. For the wall berms.

2700 sq. ft. of plastic sheeting to bury for drainage

100’ of drain pipe from gutter through barrel system to perimeter drainage

ditch

116 8” x 4” x 12” adobes for the perimeter to seal plastic roof edge

Nails

Water

Hammers,

Shovels,

Picks,

Saws,

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Measuring tape

Wheelbarrows

A hose

Hand compactor

Miscellaneous items like: rope, levels, duct tape, cutting knives, drills, nylon

string etc.

1. The Excavation

Mark the designated place for the construction before starting to dig. You

can complete the excavation by hand-digging – a method which is made easier if

done after a period of rain and the soil is softer. You can also use an ox or horse-

drawn plow, similar to the ones used by the U.S. pioneers during their early

settlement. A more expensive, but also effortless method would imply a modern

machine such as a tractor. For this latter solution, a rental would be effective as

well as hiring a professional driver for the specific machine, in order to finish the

project faster.

Do not forget to keep the removed soil in a close location. Later on, you will

need it for the berms and the rammed walls. Speaking of which, some of the

rammed earth walls can be built at the same time the excavation is going on, as

long as thesoil is very close to the construction ground. Make sure that the soil

used for rammed earth should contain approximately 10% moisture. Therefore, if

it is too dry, use your garden hose to water it a little before building the walls.

Keep in mind that you will need two channels at opposite ends of the

building to serve as future doors for the Walipini. It is important to note that all

four vertical walls of the dig need to be sloped from thebottom to the outside at

the top. A minimum of a 6” slope from bottom to top is suggested for a6’ high

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wall. This step is crucial to prevent any of the soil caving in or crumbling off from

the walls over time.

2. The Flooring

In order for the Walipini to be effective, the floor should be sloped for

interior drainage from the center to each end and the sumps dug at each end

before starting to back-fill with gravel and topsoil as explained in the previous

section.

Next, add the stones and the gravel at the bottom of the pit. A good idea is

to add an amount of organic fertilizer to the very top layer of soil that will

eventually be the seeding place for the crops.

The door jams (frames) and doors should now be installed at the bottom

level of the two ramps at the level of the growing surface. Door jams (frames)

should be of 2” thick board stock, such as 2” x 8”s, with holes drilled at the top,

middle and bottom of each side. Wooden stakes dowels, or rebar are then driven

through these six holes into the earthen wall in each jam to set the doors in plum

vertical position (use a level).

Make sure that the installed doors are airtight and no infiltration is

possible. Fill in any air cracks found around the door frames with the remaining

clay, and add sand to it to make it stick better and provide insulation. Now, you

have completed the underground stage of the Walipini.

3. The Walls

Place the walls all the way around by retreating 6” back from the edge of

the dug-out. Next, use the grade stakes as the reference and check the soil

foundation’s level next to the walls. You will have to ensure the uniformity of the

bottom level and uniform across the whole area of the construction.

By using the ramming form, lay out the walls and ram them in a straight

line. Make sure that the soil you are using contains at least 10% moisture

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material. Use a shovel to batter it and create a sturdy composition for the

enclosure.

Next, you will reach the channels that you saved for the future doors. Use a

lintel to mark each door and make sure that it is strong enough to support the

weight of the wall that will be built on top of it.

The lintel should not exceed the width of the wall. However, it should be a

foot longer on each side than the width of the door.

Now that you have ensured the doors’ positions and the strength of the

walls around them, continue ramming the first layer of earth-wall around the

construction. From time to time, take a step back and make sure that the walls

are straight. Ask for a second opinion as well. While building the inside walls, a

small inclination of the walls can be omitted and later lead to a total collapse of

the pit. So, it is crucial that the walls will be as straight as possible.

Increase the strength of the wall by adding extra material to the vertical

joints of the walls. This material should have a little more moisture than the one

used for regular ramming. Do not stop until the desired height has been reached

for each wall.

The end walls will need to be cut with shovels at the appropriate 39-40º

angle in order to allow the addition of the perpendicular roof angle that will

attract more energy from the sun during winter.

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More than that, you will need to use the shovel on the high and low walls

as well. This is because they will need some extra shaping to accommodate this

same angle, as the poles spanning the roof glazing are laid into them at 39º - 40º.

If the walls are located correctly, a 6” shelf will exist around the entire

inside of the building between the bottom of the rammed walls and the top of the

dug-out walls.

This shelf can serve many purposes, but during the ramming of the walls it

provides enough of a surface between the bottom of the wall being rammed and

the top of the dug wall to prevent cave-ins along the dug-out walls.

Now, the most difficult part of the project is finished and the Walipini

greenhouse is nearing its completion. Make sure that you have all the materials

handy for the next stage, such as the drill and the plastic sheets.

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4. The Roof

You are moving on to a phase that needs more math calculation and less

dirt on your hands. Recheck and make sure that the angle of the roof is

approximately 39º to 40º so it will be perpendicular to the sun’s position on the

winter solstice.

Next, place the twenty 4” x 16’ long poleson 4’ centers spanning the roof

beginning at one end of the growing area which will place the18th pole at the

other end of the growing area.

Poles 19 and 20 are placed at the ends 4’ from poles 1 and 18 so that there

is minimum 1’ overhang over the two doors on the ends of the building.

Little overhang on the front and back walls are needed, if plastic sheeting is

used to protect the immediate area from erosion and water penetration. Before

pinning the poles into the tops of the back and front walls, place a sheet of plastic

running the full length of the interior of the building, including the overhangs, at

both the top and bottom so that this interior glazing will be staked down with the

end of each pole.

Drill a hole in each pole and stake it into the rammed earth with rebar, a

wooden stake or dowel. Fill the wall in between each pole with adobe mudthe

width of the wall following the angle of the poles. This will seal the area between

each of the poles to prevent outside air from coming in and inside heated air

venting to the outside.

Now cover the entire exterior of the roof with the plastic sheeting

overlapping each joint at least 6” to minimize air leakage and securing each

overlap with wood stripping and nails at one of the poles. Nail stripping the full

length of each pole to secure the plastic and to prevent wind damage.

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Place a single course of adobes all the way around the perimeter of the roof

with the exception of the bottom side where the water runs off into the gutter

system. This will secure the boarder of the plastic to the walls. On the lower wall

the plastic must run down to the gutter system unobstructed so the water freely

follows this course.

Now go inside the Walipini and finish lining the underside of the poles/roof

with the plastic securing it with nailed stripping as well. Make sure to seal the

overlaps to prevent heated air and moisture in the growing area from entering

the dead 4” insulation air space.

Now check all areas where the poles and plastic join the roof for open

spaces that will leak air and fill them with adobe mud from the inside and the

outside.

At the gutter exit install a T-pipe so that water can be directed to the

nearest surface drain ditch and/or inside to the barrel water

storage/heating/overflow system.

5. Completion

You have just built your first Walipini. All it needs now is a serious planting

session of all your desired fruits and vegetables. I have prepared a description of

some of the plants that are easier to grow in an underground greenhouse, but

first you must complete a final series of checks.

Build a small fire inside the Walipini and cover it with a damp cloth to

create a sizeable amount of smoke. Get out of the pit and check for any air leaks.

If there are any, you will clearly see the smoke exiting the greenhouse. Once this

problem is solved, open the doors and let the pit ventilate naturally for a few

hours.

Before starting the planting process, seal the building to the maximum. This

will allow it to start the heat-gaining process that will be the main ingredient to

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the success of your crops. The Walipini will be ready to receive the plant seeds as

soon as the temperature reaches 40oF.

The exciting aspect of owning your own Walipini is that it becomes a

learning experience over time. You will discover your own way of dealing with

ventilation, drainage and heat exposure as well as the crops that you will plant

there.

There is no surprise about the obvious purpose of a Walipini - to grow fruits

and vegetables in a natural way, without being dependent on the outside

weather. However, there are cases in which people used underground

greenhouses to raise livestock or at least to protect it from the frosts of winter.

This says a lot about the Walipini’s range of offerings and possibilities.

Nevertheless, I bet that you are more interested in growing some delicious fruits

or nutritional greens in your newly-built pit.

Here is just a short list of fruit and vegetables that you can grow in your Walipini:

Arugula

Arugula is a highly-nutritional

vegetable that has the ability to

develop in extreme conditions and

hardened soils. This plant can be

consumed raw or cooked in various

meals. The flowers are also edible, and

can be eaten raw, or dried and used as

a tea.

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This leafy green grows quickly, and germinates in about a week. It does the

best if planted in sunny weather in the early spring, but it will tolerate most

temperatures. Therefore, it is a suitable candidate for your Walipini crop.

Beets

Beets are some of the most consumed

vegetables on the planet. This is due to

their sturdiness and year-long

availability. Almost every part of the

plant can be eaten and used medicinally.

They tolerate heat well, but prefer cooler

climates, and can withstand frost. The

taproots can be stored long term, and

can even be pickled, which is a great way

to store food.

Beetroot can be eaten raw, roasted, boiled, or pickled, so it’s versatile as far as

preparation goes.

The seeds can be planted directly into a prepared bed that’s as free from rocks as

possible.

Beets will grow in rocky soil, but too much debris can hinder the roots

progress. The less packed the soil, the better. You can save a special place for

beets in your Walipini, where the top layer is not as thick and their roots can

extend to the gravel layer below.

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Broccoli

Love it or hate it, broccoli is a must-have in your Walipini pit. It is easy to grow

and loves cold weather. It germinates well in temperatures as low as 40 degrees

F. It’s a tough plant that’s packed with nutrients, so it’s a great addition to a

survivalist’s garden. It

does need to be replanted

every year, but if you do it

right, you might be able to

get more than one harvest

out of it.

Broccoli has the highest

content of vitamin C of all

of the cruciferous

vegetables, with 135% of your daily allowance. Broccoli seeds germinate best

between 40 and 85 degrees, so plant them in the spring or fall. The seeds need to

be about a half inch down and spaced a foot apart. They prefer moist soil and full

sun, so only grow this crop if you have plenty of both.

Carrots

Carrots are a tough root vegetable that are disease resistant and can grow in

fairly poor soil.

They don’t do well if

conditions are extremely

moist and warm, as they

are prone to rot, but they

are a great vegetable for

dry, cool environments.

They are filled with

nutrients, and like almost

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all root vegetables, have a long shelf life.

Carrots grow best planted in rows and spread a few inches apart, in loose soil.

If you only have heavy soil, they will still grow, just a little more stunted than

normal. Cover the seeds with about one half inch of dirt. Don’t over water, as the

seeds are tiny and might wash away. Keep the carrot patch free of weeds and

other plants, as their root systems damage easily.

Raspberries

There are plenty of varieties of

raspberry that will suit whatever

climate you live in. They are easy to

grow, prefer neglected soil, and

will develop easily once they’ve

been established.

Raspberry bushes prefer full sun, but if you are growing them in a hot climate,

try to find a spot that has some shade in the afternoon. Red raspberries do better

with something to climb, but the black and purple varieties are bushy and need

more room. The soil should be well aerated.

Strawberries

Strawberry plants aren’t known

for being tough and easy to grow

in the garden, but they make a

great houseplant. In fact, they are

one of the few fruits that can be

grown indoors, which is what

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makes them a good choice for a survivalist.

Strawberries have been used for thousands of years as a medicine to treat

gout, jaundice, and rheumatism.

Strawberries have an extremely shallow root system, so you can use just about

anything to plant them in. You can buy a strawberry tower or make your own,

which will use the least amount of space and give you the most yields. If you are

growing from seed, use a seed tray to get them started. Sprinkle the seeds into

soil and cover them with a loose layer. Use a spray bottle to water them. Once the

seedlings grow a third leaf, they can be replanted in pots or a tower.

Kale

Kale is a hardy green that can

tolerate both heat and frost.

Some plants will even continue

to produce leaves during the

cold winter months, and can

grow in 20 degree weather. It’s

also considered to be one of the

most nutrient dense edibles on

the planet.

It’s considered a superfood, with very high levels of vitamin C, A, and K, and

most of its fat content comes from omega 3. This is one of the most nutritious

plants out there and it would be a great addition to your underground Walipini.

Sowing the seeds in the spring will give you the best results, but they can also

be sown up until August. They don’t need any help growing. Just give them water

every once in a while. They will start producing leaves about a month after

they’ve been planted.

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So, there you have it! Your very own Walipini: a crucial source of fresh

vegetables and fruit for any serious survivalist out there.

An underground greenhouse is a viable project as long as you keep it in

good condition. Therefore, make sure that the walls, the doors and both the

ventilation and irrigation systems are working at all times. Care for the crops on a

daily basis and instruct a friend of a neighbor to watch over them whenever you

have to leave home for an extended period of time. From now on, you will no

longer have to depend on the above ground weather to provide healthy meals for

your family.