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As a gardener in the sweltering Texas heat, I’m already bracing myself for the inevitable watering struggles that come with spring. Wherever you are I’m sure you know the struggles of keeping your plants hydrated and happy during spring and summer.

Every year, it’s an uphill battle against the relentless heat, and those porous grow bags don’t make things any easier. But this season, I stumbled across a game-changing solution that has me counting down the days until I can set up my olla watering system.

Ollas, or terracotta ollas, are an ancient irrigation technique that’s been used for centuries in arid regions to conserve water and provide consistent moisture to plants. These unglazed clay pots, buried in the soil with just a small opening at the top, act as self-watering reservoirs that slowly release water directly to the roots.

And the best part? Not only are they ridiculously inexpensive and simple to set up, but they promise to transform your watering routine from a daily chore into an occasional task.

With olla watering, your containers will receive a steady supply of moisture, allowing your plants to thrive without the stress of drought conditions.

Can you imagine the freedom of not having to constantly worry about your plants wilting in the heat? Let’s see if its too good to be true.

What Is An Olla?

At their core, ollas (or ollas watering pots) are simply unglazed terracotta clay pots designed to be buried in the soil, with only a small opening left exposed at the top.

Simple, right? But don’t let their appearance fool you – these terracotta pots have been instrumental in helping civilizations thrive in the world’s driest, most unforgiving climates for centuries.

Ollas have their roots (pun intended) in ancient arid regions like the American Southwest and Mediterranean, where gardeners and farmers had to get creative with conserving every precious drop of water. By burying these porous clay vessels in the earth and filling them from the top, they created an ingenious underground irrigation system.

Here’s how it works: as the olla slowly releases water through its permeable walls, it delivers moisture directly to the plants’ root zones on an as-needed basis. Remember, ollas need to be made of unglazed terracotta clay to allow water to slowly seep through the porous walls. Don’t grab those glazed decorative pots!

Benefits of Using an Olla Watering System

Now that you understand the brilliant simplicity behind ollas, let’s explore the benefits.

Water Conservation

Compared to traditional surface watering, ollas are true water conservationists. While a significant portion of that precious H2O gets lost to evaporation or runoff with top waterings, ollas deliver moisture directly to the soil and roots. Say goodbye to that wasteful cycle! By reducing water loss, you’ll be amazed at how much less you need to refill your ollas.

Moisture Level Just Right

We all know plant health hinges on getting that moisture level “just right” – not too much, not too little. With olla watering, your containers will maintain a consistent, optimum level of soil moisture. No more wildly fluctuating between drought and dowsing! This steady supply of hydration allows your plants’ roots to thrive and establishes an ideal environment for growth.

Flourishing Plants

When you eliminate moisture stress, your plants simply flourish. An olla watering system provides the perfect conditions for strong root development, vigorous foliage, and bountiful blooms or productive yields.

A Lazy Gardener’s Best Friend

Raising my hand high over here – I definitely don’t enjoy the daily watering slog, especially in scorching summer! I’m also no stranger to a lazy gardening hack and simplifying your gardening routine. With ollas doing the heavy-lifting of moisture maintenance, your watering responsibilities will be reduced to an easy-breezy refill every few days or weekly. More time for margaritas and less for watering marathons?

Choosing and Prepping Ollas

When selecting your olla watering system, size is crucial based on the size of your containers and plants.

I’ve decided to go with the offerings from The Olla Company – they have a great variety of sizes perfect for all types of container gardens.


The size of your ollas should correspond to the diameter of your container and the spread of your plants’ root systems. The Olla Company makes it easy with three versatile sizes:

The Mini (2 pack) is ideal for small containers up to 1 ft wide. These 3″x6″ terra cotta pots hold 0.35 liters (12 oz) of water.

For medium-sized containers around 2 ft wide, the Classic Small at 5″x7″ is perfect. It holds 1 liter (1.06 qt) to keep roots hydrated.

Got some larger raised beds or grow bags up to 3 ft wide? The Classic Large 7″x9″ ollas with a 3 liter (3.17 qt) capacity have got you covered.

When setting up your ollas, bury them with just the top inch or two of the opening sticking out above the soil level. Position them near your plants’ root zones, going about 2/3 down into the soil for most veggies and annuals. Larger perennials and trees may need them a bit deeper.

DIY Olla Watering System

Creating your own self-watering olla system is totally doable with just some basic supplies.

For the DIY route, you’ll need some unglazed clay pots from your local garden center or hardware store. Terra cotta is ideal since it’s porous and allows water to slowly seep through.

Choose pots sized appropriately for your containers, from small 6-8 inch pots for individual planters up to larger 10-12 inch ollas for raised beds.

You’ll also need:

A drill or hammer and nail to punch a drainage hole in the bottom
Waterproof tarp, landscape fabric, or coffee filters to cover the drainage hole
Souffle dish or pot saucer to act as a lip cover (optional)


Olla Assembly

Use the drill or nail to punch or create a drainage hole in the bottom of the pot.
Cover that hole with a small square of waterproof fabric, tarp, or even a coffee filter secured by the pot’s lip. This allows water to slowly release.
If desired, you can place an oven-safe dish or pot saucer upside down over the top opening to create a fitted lid and reduce evaporation.

Limitations and Tips For Olla Irrigation

While ollas are incredibly effective for watering small to medium-sized plants in containers, they do have some limitations when it comes to larger specimens or those with extensive, deep root systems.

For smaller annual plants, vegetable crops, and portable containers up to a few feet wide, ollas provide the perfect amount of supplemental irrigation directly to the root zone. The olla’s water reservoir is ideal for maintaining consistent soil moisture for these types of plants. However, larger plants have bigger water needs that a single olla may struggle to meet.

Very large trees, shrubs or perennials can have root systems that extend much farther than the olla’s reach and water dispersion area. In these cases, you may find that one or even several ollas don’t provide adequate water for the entire root zone. The plant’s substantial size simply demands more water than the olla can slowly deliver from its underground reservoir.

Similarly, plants with extremely deep or expansive root structures like mature trees or shrubs may require supplemental watering in addition to olla irrigation alone. As the root system grows larger over time, it can eventually outgrow the olla’s ability to sufficiently hydrate all the roots from its localized placement in the soil.

To accommodate bigger, deeper-rooted plants, you may need to pair your olla system with other watering methods like drip irrigation lines, soaker hoses or even manual watering at times. Or you could try installing multiple ollas around the plant’s root zone. The key is monitoring moisture levels and adapting as your plant’s water needs change.

Nothing partners better with olla irrigation than a thick layer of organic mulch over your soil’s surface. I’m talking bark, leaves, straw – whatever mulching goodness you prefer.

Will You Try Olla Watering?

Whether you’re an experienced container gardener or just getting started, olla irrigation is a technique worth trying. This ancient method provides such an easy low-maintenance solution to one of the biggest challenges we face – keeping our plants consistently hydrated.

By burying these clay pot reservoirs into your containers and garden beds, you’re tapping into a sustainable hack for delivering water directly to the root zones with virtually no runoff or evaporative loss.

Can you imagine having a self-sufficient watering system that eliminates drought stress and overwatering? With ollas, you finally can!

If you try it, let me know how it goes!

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