(air whooshes)
- This is a terracotta clay face.
I'm gonna bury it in my garden
and I'm gonna show you why it just might be
one of the best passive irrigation systems you'll ever use.
What I have in front of me today are ollas.
These two over here are ollas.
These will become ollas
as I show you how to build a DIY one later in this video.
But what is an olla?
Well, it is a passive irrigation system
thought to have been originated in northern Africa.
In China, there are records
going back over 2,000 years for ollas.
And the Spanish, since I live here in San Diego,
are thought to have brought it in to the Americas,
where it's become popularized,
especially in Mexico and the native peoples in pre-Mexico.
So why is this such a fantastic system for watering?
Well, in dry lands, in drought-stricken areas,
much like we have here in San Diego,
a buried, unglazed clay pot
is a tried-and-true method
for making the best use of the water that you have.
So let's take this little clay face
and I'll show you exactly how it works.
(pot clanks)
It's an unglazed terracotta.
Unglazed because you actually do need seepage
out of this material.
This is a porous material that slowly does let water
get out to the exterior that you've poured inside.
So that's key number one.
Number two is the narrowed neck
helps with evaporation loss.
So it's a narrow neck.
There's not that much up here at the top,
'cause it's gonna seep upwards as well,
for it to then get evaporated
and go into the air, not into the soil.
And then number three,
the real strategy here is, here's your soil level.
You bury it down, you fill it up with water.
The water slowly seeps out.
If the soil needs that water,
it's basically going to suck the water off of this surface.
And roots, actually,
if you plant a plant near it or around it,
and we'll get into a couple different layouts you can use,
it will actually grow around
and the roots will sort of suck the water
right off of this surface here.
So it's an incredibly effective use of water in the garden.
So a few advantages to using ollas
compared to other systems,
or maybe even in tandem with other systems.
Number one, if you are a gardener or a farmer
who really likes to direct sow your seedlings
and then you know they need a lot of moisture
as soon as they come up,
I'm thinking things like maybe carrots or tomatoes,
you can go ahead and direct sow in rings around an olla,
knowing that
they're actually going to get the water they need,
so you don't freak out
and it doesn't wither as soon as it germinates.
One big benefit there,
for vegetable growers, like myself,
and hopefully a lot of you watching,
you can save up to 50% to 70%
of your water use that you would traditionally irrigate,
let's say, if you had an overhead hose.
You're gonna get a lot of benefit from that.
And then you can use things like your laundry water.
You can use things like your sink water.
If you have an outdoor sink,
take that gray water and fill up your ollas.
And speaking of, you're probably wondering,
"Okay, cool.
How much does this actually spread out?
How much space does this cover?
And how do I actually plan a garden
around the use of ollas?"
So let's take this directly into the garden.
The way to think about an olla
is not so much how big the olla itself is,
it's how big the spread of water seepage around the olla is.
So we have a chart that displays roughly,
based on the diameter of the olla,
how far it actually spreads out.
So call this about a six-inch across olla,
it's going to have a diameter of 9.5.
So that's diameter.
That means that on each side,
it's gonna be roughly 4 1/2 to 5 inches spread.
So when you put this down into the garden,
let's just imagine I'm placing it right here,
you only have that spread to play with.
Otherwise, the water is simply just not going to reach.
So what you need to do when you're placing an olla,
especially in, let's say, a round bed like this,
is you need to place it in an area that has maximal spread.
So obviously, right in the center
where this basil's hanging out would be the ideal spot,
and then plant plants around it,
roughly half the distance of that spread.
So I would plant very, very close to this olla.
It's only gonna come out to about here or so,
but in a container, that's actually perfect.
And then I'd cut that in half and plant around it,
based on the plant spacings that you're growing
for whatever plant it is.
So with beans, peas, et cetera,
you'd space them around in sort of a circle
and you'd be in a good spot.
Now if you were gonna put these in a series,
in some sort of rose-style garden,
or maybe in one of our larger raised beds,
then what you want to do is play with this diameter.
So I know I have about five inches on this one,
five inches on this one,
so 10 inches here is roughly how I want to space them.
And then you can put plants
anywhere in that circle of spread that you're building.
So when you have multiple ollas,
you just want to make sure
that you're not crazy overlapping the spread,
but you're also not leaving any wide gaps.
So let's show you how to actually bury one
and use it in your garden.
I've got this incredible in-ground bed here,
and I'm just gonna site it
right in the middle, for simplicity's sake.
But of course, remember everything we just said
about olla spacing.
So what I need to do is get it down
to roughly here, (pot clanks)
if not a little bit more.
But going right at that narrow neck is is perfectly fine.
So what I'm gonna do is just dig in.
So I'm just going to dig out
as much as humanly possible here,
to make sure I have a nice snug fit.
In goes our face.
(olla lid rattles)
I think we're in a good spot right about there.
Now what I want to make sure and do is backfill around,
'cause remember, the soil needs to be touching
the actual clay
for it to have that seeping or that suction effect.
(upbeat music)
Now that we have our olla buried,
just wanna pop the top off and fill it up all the way.
(upbeat music)
There we go.
Top always remains on.
You do not want this to be a breeding ground for mosquitoes.
So a couple things here.
You need to make sure and refill it as it gets drained,
not all the way down.
So at about 50% or so, you're gonna wanna refill it.
That might mean it's a daily job for you.
It might mean it's a weekly job for you.
Depends on the qualities of your soil,
the plants that are growing around it,
as well as the size and diameter of your olla.
So a little bit of gardener's wisdom there.
And then if you are in a cold climate,
it's a good idea at that frost date
to dig these out, clean 'em off,
and put them in an area
that they're not going to be subjected
to a ground freeze and thaw, and freeze and thaw,
which of course with terracotta, makes it prone to crack.
Now, these are prepared ollas.
These are manufactured ollas.
These are actually handmade in Mexico
by an incredible company.
We offer them on our store.
But you might not want to do that.
You might just want to DIY an olla.
So I'm going to show you how to do that right now.
If you want to make your own olla, it is certainly possible.
I'll give you two really easy methods,
but I will say, it simply isn't going to perform as well.
Doesn't mean you shouldn't do it,
but these are purpose-made,
and the reason why they work so well
is 'cause that narrow top prevents a lot of evaporation
at the very top,
which means you just have to fill it less often.
But let me show you two methods.
The first one requires one terracotta pot, one lid,
and a little mounting putty.
So this is from
Gorilla Glue. (package crinkles)
All you're gonna do here is grab some of the putty,
just enough to fill
the bottom drainage hole.
Better yet, maybe a pot that doesn't have a drainage hole.
Still has to be unglazed terracotta, though.
So in we go.
Once it's set,
you can actually flip this upside-down,
fill it up with water, dig a hole out,
and then lid goes right side up.
Boom. (lid clinks)
And you have a makeshift olla.
Now of course, with this amount of surface area,
it is gonna need to be filled up a little more often.
You don't have quite as much, but hey,
it requires a lid, a pot, and some putty.
So you're good to go on a budget olla.
Now let me show you another method
that gives you a little more surface area
and is maybe a bit more true to the spirit of the olla.
So what you need here, two terracotta pots and that's it.
What you're gonna do
is with either silicone or mounting putty,
I'll just use mounting putty because it's very simple,
you're going to plug up the bottom hole
of the one that's on the bottom.
So I'm gonna choose this one for my bottom.
And now,
we want to take it and stack it just like this.
I'm gonna actually turn it this way,
'cause that's the way that it would be faced
in our olla situation.
And what you want to do here
is take a caulking gun with some silicone,
waterproof, watertight, all that kind of stuff,
and come around the edge here
and lay a bead
of silicone
around this entire system here.
Once your DIY topsy-turvy olla is sealed off,
the silicone has dried,
all you really need is to just bury it,
much like I've already showed you.
Grab something, I just have a little pebble here,
to block the top,
make sure no mosquitoes get in, make sure less evaporation,
and you have a much larger olla.
So the spread here and the water volume
are a lot larger and it's still a DIY.
So whether you're grabbing a pre-prepared olla,
I'm absolutely a huge fan of this large one,
then the small one with the face is just kind of cute,
or you're making your own,
try to think about different ways
to irrigate your garden passively and effectively.
And until next time,
good luck in the garden
and keep on growing.