Ollas by Kleipots - Waterwise

Amelia Jacobs, Devil’s Peak Estate, Cape Town

Ancient terracotta watering system for the urban garden

An irrigation method using clay pots that are buried under ground

OLLA

SAY "OH-Yah"

Ollas are terracotta clay vessels that have been used for irrigation by agrarian peoples for centuries. The unglazed pots are simply buried in the soil with the neck sticking out. They are filled with water that slowly seeps out to the roots of the plants. The roots in turn “embrace” the olla and extract the precious moisture as needed.

Olla shapes and sizes
Cape Town gardeners use ollas in planters
olla pottery watering system terracotta
An olla waters the soil inside an earthenware pot in Cape Town

Why use ollas in your garden?

  • Because an olla dispenses water directly to the roots, there is no wastage, and minimal evaporation from the opening of the jug peeping through the surface of the soil.
  • Ollas prevent overwatering – a common problem with veggie gardening and pot plants.
  • Ollas are waterwise. You’ll be contributing to saving this precious resource. The olla diffuses water into the soil as and when the plant needs it.
  • An olla waters when you can’t. Fill all your ollas before going away for a few days. Your plants’ watering needs are taken care of!
  • Because ollas supply moisture underground near the root system, it discourages weeds from propagating on the surface, which remains relatively dry.
  • Ollas help to keep the soil aerated. It prevents the soil from compacting, which occurs with conventional watering methods.
  • An olla can be used as a booster when establishing new saplings or shrubs: bury an olla near the sapling until it is nicely settled. You can then retrieve the olla and use it elsewhere in your garden.

The origins of the olla

The word “olla” was derived from the Latin “aula” or “aulla” and refers to a rounded clay pot that was used for a variety of purposes including subterranean irrigation.

4 Olla terracotta jars in a row
Ollas have been used for irrigation all over the world for centuries; they are found in all shapes and sizes in the more arid regions of North Africa, the Levant, Asia and the Americas. It is believed this practice dates back more than 4 000 years. The oldest known written instruction on the use of buried, unglazed clay vessels for irrigation was in the “Fan Shengzhi shu”, a Chinese agricultural guide from the Han dynasty (202 BC – 220 AD).
I have been using ollas for many years.
Since lockdown I have been a busy bee in my garden and had this idea to design and make my very own. Ollas are suitable for medium/large pots or can be buried directly in the garden or containers.
They are practical, affordable and very effective.

ANCIENT WISDOM FOR THE MODERN GARDENER

How to use your olla

  • Simply bury the olla in the soil with the neck sticking out and fill it with water. The water will slowly seep through the porous clay into the soil and stimulate root growth.
  • Cover the neck with a flat stone or shard to discourage insects or soil from getting in. (I use champagne corks on my regular ollas.) Each of the large 2,6-litre ollas has a unique raku-fired crown stopper for this purpose. Covering the neck also helps to minimise evaporation in hot weather.
  • Check and top up your ollas regularly, usually every few days. Do not wait until they are empty; the idea is to keep the soil moist without saturating it. In hot weather the ollas can run dry very quickly.
  • The olla will only release water on demand, so it is impossible to “overwater”.
  • The time it takes for the water to dissipate depends on soil type, plant species and weather conditions. It is advisable to establish this before leaving the plants unattended for a prolonged time.
  • Add plant food directly to the soil, not into the ollas.
Olla terracotta irrigation demo y Kleipots Cape Town
Olla with a large belly
An olla slowly releases water into the soil.

Buy ollas

If you’d like, you can contact me directly. Use the form or simply WhatsApp me on 083 303 6025.

An olla (or two) makes a thoughtful gift for someone who loves a well-kept garden.
Olla with a half belly
Half Belly Olla holds 400 ml water. It's 190 mm high and 90 mm in diameter.
Olla Round Belly
Round Belly Olla holds approximately 450 ml. It stands 190 mm tall and is 115 mm in diameter.
Olla with a tiny belly
Tiny Belly Olla holds about 100 ml. It's 185 mm tall and 55 mm in diameter. Slim enough for a smaller pot or planter.
Olla terracotta large with stopper
Each Large Belly Olla comes with its own unique raku-fired crown stopper. Holds 2,6 litres. 260 mm H x 175 mm dia.