Do Diy Ollas Really Work?
What is a DIY Olla?
An olla (pronounced oy-yah) is an unglazed clay pot that is buried in the ground and used as a very efficient irrigation device. Ollas originated centuries ago in Africa and the Middle East before spreading to the hot, arid regions of Mexico and the southwestern United States.
The traditional olla utilized a raw clay pot with a narrow neck and wide base. The porous terra cotta allowed water to slowly seep into the surrounding soil without losing much to evaporation. Ollas were filled manually by hand.
Today, a DIY olla can be made by drilling a hole near the base of an unglazed terra cotta planter and burying it up to the neck in soil. Water is filled through the top, seeping out through the terra cotta to water plants’ roots with minimal evaporation. DIY ollas are a thrifty and low-tech way to irrigate garden beds and potted plants.
How Ollas Work
Ollas are an ancient form of irrigation that utilize unglazed terra cotta to slowly release moisture to plant roots. The porosity of the terra cotta is key to how ollas work. When an olla is buried in the ground near a plant and filled with water, the terra cotta clay gradually allows water to seep through the pot walls. This creates a reservoirs of moisture in the surrounding soil for the plant’s roots to uptake as needed.
The terra cotta clay is an ideal material because its pores control the release of water through capillary action. The small pores only let water molecules pass when the soil surrounding the olla becomes dry. As the soil dries out, it draws more water from the olla’s terra cotta walls. This creates a self-regulating system powered by the soil’s moisture levels rather than relying on any electrical pumps or drip irrigation equipment. Ollas provide a simple, low-tech way to irrigate plants.
Benefits of Olla Irrigation
Ollas provide several key benefits compared to other irrigation methods:
Efficient Water Use
Ollas deliver water directly to the plant’s roots through a small opening, minimizing evaporation and runoff. This allows plants to get more water from less overall usage. Ollas only release small amounts of water as the soil dries out and roots draw in moisture.
Self-Regulated Moisture
The terra cotta clay naturally absorbs moisture from the surrounding soil. When the soil dries out, the clay releases water to maintain an ideal moisture level. This creates a self-regulating system to water plants just the right amount.
Less Evaporation Than Drip Irrigation
With drip irrigation, water is exposed to air as it moves from the drip line to the plant’s roots. Ollas deliver water underground directly to the root zone, minimizing evaporation losses.
Challenges of Ollas
While ollas provide an efficient and low-maintenance form of irrigation, they do come with some challenges to be aware of:
Placement and Burial – Ollas need to be buried at the proper depth and location near the plant’s roots to work effectively. Placing them too shallowly or too far from the root zone will impede water absorption.
Checking Water Levels – The water levels in ollas can be difficult to monitor since they are buried. You’ll need to periodically unearth them to check if they need refilling.
Preventing Algae and Clogs – The humid environment inside ollas can promote algae growth and clogging over time. Use cleaning methods like scrubbing or bleach to remove any buildup and keep ollas functioning properly.
Best Plants for Ollas
When selecting plants to use with DIY ollas, it’s best to choose varieties that thrive in warm, dry conditions and don’t require frequent watering. Some of the top options include:
Tomatoes – All types of tomatoes do very well with olla irrigation, including cherry, roma, beefsteak. The confined watering helps prevent splitting. Tomatoes are heavy water users, so ollas provide an ideal option.
Peppers – Peppers are another warm weather crop that benefits from an olla. The consistent moisture produces excellent results for varieties like bell peppers, chili peppers, poblanos and more.
Eggplant – Given eggplant’s Mediterranean origins, it’s no surprise they thrive with olla irrigation. You’ll get great yields with consistent moisture at the roots.
Herbs – Herbs like basil, oregano, thyme and rosemary grow very well with ollas. The confined moisture helps prevent fungal disease in many herbs.
Flowers – Bright flowers like marigolds, zinnias, cosmos, and sunflowers can also be watered via ollas. Create a self-watering flower bed for continuous blooms.
Setting Up DIY Ollas
Setting up DIY ollas is relatively straightforward once you have gathered the necessary supplies. Here is what you will need and how to assemble your own olla irrigation system:
Supplies Needed
To make a DIY olla, you will need:
- An unglazed terra cotta pot, ideally 1-2 gallons in size
- A plastic bottle or jug that fits snugly into the terra cotta pot’s opening
- Play sand, pea gravel, or marbles to fill in around the jug
- A shade cloth or burlap to cover the olla’s opening
Instructions for Assembling
Follow these steps to assemble your olla:
- Rinse out the plastic bottle and allow to dry fully.
- Fill the bottle with sand, pea gravel, or marbles, leaving 2 inches at the top empty.
- Insert the filled bottle snugly into the opening of the terra cotta pot.
- Surround the bottle with more filler material so it stands upright in the pot.
- Cut a square of burlap or shade cloth slightly larger than the pot’s opening.
- Wrap and tie the fabric over the opening to prevent evaporation but allow water to seep through.
Tips on Placement and Filling
When placing and using your olla:
- Position it near the plants you want to irrigate, buried in the soil with just the top exposed.
- Fill the bottle fully with water to start the seepage process.
- Refill every 2-7 days depending on your climate and soil type.
- Avoid overfilling, which can cause the water to come out too quickly.
Maintenance Tips
To get the most out of DIY ollas, be sure to follow these maintenance tips:
Checking Water Levels
Periodically check the water level in the olla. Lift the olla gently to see if it feels light and empty or still heavy with water. Refill any ollas that feel light. A good rule of thumb is to check water levels at least once a week.
Cleaning Mineral Deposits
Hard water can leave mineral deposits on ollas over time. Make a solution of one part vinegar to four parts water. Remove the olla, give it a good scrub with the vinegar solution and a bristle brush to remove any scale buildup, then rinse thoroughly before returning.
Winterizing
In cold climates, be sure to remove ollas in the fall so ice does not cause them to crack. Store ollas indoors over winter and replace them back in the soil each spring.
Comparisons to Drip Irrigation
When it comes to efficient water use, ollas have some advantages over drip irrigation. Because ollas supply water directly to the plant roots through the buried clay pot, they help minimize water loss from evaporation. Drip irrigation systems water the soil surface where some water can be lost to evaporation before being absorbed by the plants.
Ollas also require less infrastructure compared to drip irrigation. A basic olla setup just needs the buried clay pots whereas drip irrigation needs a network of tubing, emitters, and timers. This makes ollas a simpler, more affordable option.
The trade-off is that ollas have higher labor requirements. Refilling the ollas has to be done manually on a regular basis, versus a drip system that can be programmed and automated. So while ollas are less complex to set up initially, they do demand more frequent, hands-on maintenance over time.
Results to Expect
Using DIY ollas can provide several benefits in your garden or yard when properly set up and maintained. Here are some of the key results you can expect from using ollas:
Increased Yields
Ollas provide a slow, steady supply of water directly to a plant’s roots. This consistent hydration supports better growth and higher yields compared to traditional top-watering methods. Studies have shown olla-irrigated plants can produce up to 25% higher yields.
Healthier Plants
The regulated water supply from ollas prevents overwatering, allowing plant roots to access just the right amount of moisture. This helps plants grow stronger, with less disease and fewer nutrient deficiencies.
Less Water Usage
Ollas deliver water slowly and directly to the roots, reducing evaporation, runoff, and waste. Most olla users report using at least 20-30% less water while achieving better results. Less frequent refilling also saves time and effort.
With the right setup and maintenance, DIY ollas can certainly provide impressive results in many gardening situations. The key is following best practices tailored to your specific plants, climate and soil. Evaluating your results season by season can help perfect your olla irrigation system.
The Bottom Line
After reviewing the pros and cons of DIY ollas, it’s clear they can be a useful tool for watering plants, but may not work in every situation. Ollas excel at slowly releasing water over time, reducing evaporation, and minimizing the amount of water needed compared to frequent top-watering.
However, ollas require some trial and error to get the fill level and placement right. The buried ceramic vessels also demand a little more effort to set up initially. While ollas can work well for small gardens, containers, and potted plants, they may become unwieldy for expansive gardens with large watering needs.
The bottom line is that ollas deserve consideration alongside other irrigation methods. They offer unique advantages that make them a wise choice for many gardeners, especially those growing plants in hot, dry conditions. However, those with large gardens may find the maintenance required makes ollas impractical.