Why Do Terra Cotta Pots Have Holes on the Side? (5 Reasons)
Living in a hot and dry region, I’m most familiar with terra cotta pots that have single drainage holes at the bottom. A few years back, however, I came across interesting clay containers with holes on the side. At first, I was puzzled, but now that I know what they’re and why the holes are there!!
Some terra cotta pots have holes on the sides to 1) collect water, 2) improve drainage, 3) ensure aeration, 4) promote rooting, 5) increase usable space, and 6) double as a decorative piece. They are often used to grow specific plants like orchids, herbs, strawberries, cacti, and succulents.
Planter holes aren’t actually needed for drainage alone. They serve a myriad of functions that you may need if you want to propagate good cuttings or grow multiple herbs in a single pot. However, they aren’t perfect. Find out the potential drawbacks of side holes!
1. Collect Water
Rather than having a drainage hole in the middle of a terra cotta pot’s base, some have elevated side holes so that water is collected at the bottom. This is ideal for plants that require consistently moist soil such as vines and ferns.
As you probably know already, all unglazed clay planters are naturally used for more drought-tolerant plants that can handle high temperatures and very little watering. This, however, doesn’t mean that you need to buy plastic pots for plants that need more moisture.
In other words, those terra cotta pots with side holes you may spot in gardening and home improvement centers have a built-in water reservoir at the base.
Terra cotta pots with holes on their sides are made specifically to store up to 1–2 inches of water at the bottom of the pot while letting excess water drain out.
Such a reservoir also lessens the need for frequent watering, even if you live in a hot and dry area like Arizona.
Every time the soil starts to dry up, the water at the reservoir will help make it moist once again until it all runs out. Be sure to check for soil moisture and water accordingly.
With this, you won’t have to worry about your plant’s growing medium completely drying up!
Unglazed clay pots like terra cotta, with raised side holes, are great for the following plants:
- Cast iron plant
- Trumpet creeper
- Spiderwort
- Climbing hydrangea
- Painted fern
- Ostrich fern
- Autumn fern
- Rainbow moss
- Hardy hibiscus
- Siberian iris
- Mints
2. Improve Drainage
A terra cotta pot with holes at the bottom and the sides is designed to improve drainage. The collection of standing water is avoided with additional side holes.
More often than not, terra cotta pots with bottom drainage holes don’t have legs. Even when placed in a cache pot or on a catch plate, excess water may not completely get drained from these pots—especially if they are set directly on the floor or ground.
You would have to place some gravel, bricks, and other similar materials to prop it up and allow water to freely spill out of its hole at the bottom. On the downside, doing this can take away from the aesthetic appeal of having lush green plants on clean terra cotta pots.
So I can totally understand why you wouldn’t want to do that. In such cases, if you still want to avoid leaving your plants in soggy or wet soil, then I suggest you use terracotta pots with side holes—regardless of whether they already have a bottom drainage hole or not.
As early as the 1800s, terra cotta flowerpots with multiple extra drainage holes along the sides were already used in England. There they were simply called kitchen pots.
Using a pot with additional drainage holes like this will save your plants from sitting in a puddle of water all the time. In turn, you can also avoid root rot!
3. Ensure Aeration
Side holes on terra cotta pots ensure sufficient aeration in growing mediums. As a direct result, the growth of unwanted harmful bacteria that can kill plants is avoided.
Proper aeration is not always guaranteed even if there’s a drainage hole at the bottom of your clay pot.
Sure, unglazed terra cotta can let some air penetrate its walls and reach the growing medium. But this is not always the case.
Just as I’ve mentioned previously, it’s not enough to have one hole at the base of a planter—even more so, if it’s a legless glazed terra cotta pot that’s placed on flat ground.
In comparison, terra cotta planters with at least 3–4 side holes like the one below from Amazon will get better airflow. When these holes are placed opposite each other, the air is guaranteed to pass through and keep your lovely plants’ mediums aerated!
This is essential for keeping plants lush and thriving. You see, soil that doesn’t get enough airflow is likely to become aerobic, making it the perfect breeding ground for bad bacteria.
Learn more about anaerobic soil in our article on whether potting soil goes bad.
4. Promote Rooting
Terra cotta pots with numerous side holes can be used for propagating cuttings and seedlings with well-developed root systems. Nowadays, however, plastic air-pruning pots are more commonly used.
A common issue with container plants is their tendency to get root or pot-bound. By using a terra cotta pot with numerous little holes, however, this can easily be prevented!
Unlike plants grown in regular pots that only have a hole at the bottom for drainage, plants propagated and cultivated in pots with several side holes develop better roots.
Rather than growing down continuously before circling the pot as they grow, roots in pots with holes all around their walls grow fibrous and develop multiple branches without spiraling.
Gardening expert call this air-pruning. When roots start poking out of the hole and get exposed to dry air, they basically trim themselves off and induce branching from within.
This allows young plants to better handle environmental changes after they are transplanted directly into the ground. Because of their well-developed branching roots, taking up water and nutrients from the soil is easier!
5. Expand Usable Space
Deep terra cotta pots with big holes and pockets around the sides have more space to allow for growing one or more plants of the same or different species in one planter.
Terra cotta pots with open pockets around the sides, like this one from Walmart, are nothing new. You probably won’t have a hard time looking for them in plant nurseries.
Although they are often referred to as strawberry planters, you aren’t limited to only growing those delicious red berries in such a terra cotta pot.
You can grow a variety of different plants in strawberry pots including, but not limited to, cacti, succulents, herbs, and ornamental flowering plants. What makes them even better is can cultivate different plants using only one pot as long as they have similar growing needs.
Choose which plant to grow together in our article on companion plants for basil!
So if you want to have a mini herb garden on your balcony, a terra cotta pot with several pockets will be the best option for you. They’re a great space-saver that will give you more usable space for a lot of gorgeous plants!
When you want something more colorful or polished-looking, try searching for ceramic strawberry pots. Besides that, you might also want to look into stackable plastic pots.
6. Double as Decoration
Terra cotta pots with side holes can double as decorative pieces when different colored plants like succulents are kept in different pockets of a single planter.
As superficial as this might sound, you can’t dismiss the fact that having an attractive planter will always be a put whether they’re placed indoors or kept outdoors.
Just like I said in the previous section, strawberry planters aren’t used just for growing sweet fruits. Most people I know typically use them for vibrant succulents, cacti, and other ornamental plants.
You don’t even need any knowledge or experience in flower arrangement to create a beautiful centerpiece for your patio table or balcony. So if you want to maximize your use of space while making a statement, try this out!
4 Downsides of Terra Cotta Pots With Side Holes? (Solutions?)
Despite its numerous benefits, the drawback of using terra cotta pots with side holes include 1) standing water, 2) too much water loss, 3) water spillage, and 4) growing medium spills.
Now, I know that some of these sound quite contradictory, but stay with me!
As I’ve mentioned before, terra cotta pots with side holes come in various designs. Depending on which one you may only have to deal with 1–2 of these issues. Let’s explore them!
1. Excessive Draining
Unglazed terra cotta pots with big drainage holes not only at the bottom but also at the sides—in multiple rows—are bound to get bone-dry in a flash.
When we also consider local climates, your plants may end up drying up and dying completely much faster in arid regions.
Solution
If you live in a dry place and you need a planter that’s going to keep your plant’s growing medium moist enough, look for a clay pot with fewer holes.
You can also place a multi-holed terra cotta pot inside a larger pot to prevent excessive draining.
2. Standing Water
Not all plants love getting water every single day. This is true for most succulents and cacti. I would know since I have killed a few due to overwatering when I was younger.
Don’t grow any dry-soil-loving plants in terra cotta pots with a water reservoir. Their elevated side holes will prevent their growing medium from draining completely.
Solution
Put rocks or gravel at the bottom of your terra cotta pot that only has a few small elevated side holes. This will prevent water from accumulating at the bottom, ensuring drainage.
Alternatively, you can drill drainage holes at the bottom of your clay pot—more on this in the next section.
3. Water Spill-Out
Terra cotta pots, no matter how beautiful they are, can look quite unsightly when the plants in them are being watered. My friends and I don’t like using them for indoor plants for this very reason.
In general, we wait for the water to start draining out of the holes to tell that we’ve given them enough water right? For bottom holes, this doesn’t really become an issue. But it’s the opposite for terra cotta pots with side holes—regardless if there’s only one row or not.
Water leaves streaks all around the sides after they are watered. It’s also pretty much impossible to avoid spilling water when you are watering plants in these containers.
Solution
Make sure to have a dedicated saucer for each of your terra cotta pots with side holes. You can also use a large tray while watering plants in clay pots that have multiple side holes.
Even though you won’t be able to avoid the water streaks either way, you can—at the very least—still make sure that all the excess water can easily be contained and disposed of.
4. Medium Spill-Out
A growing medium that has small particle sizes can easily and quickly spill out of the several big holes of specific designs of terra cotta planters such as orchids or kitchen pots.
I have seen some people suggest plugging these holes with broken pieces of clay and rocks. The thing is, doing that would only give you a new set of problems altogether—standing water and lack of aeration.
Solution
What you should do instead is line your planter with a fine plastic mesh or some landscaping fabric. Just make sure that the patch is larger than the hole so that no medium will spill even if it does move over time. You could also completely line your container just to be sure.
How Can You Drill Holes Into Terra Cotta Pots?
Battery-powered drills with diamond drill bits can be used to make clean drainage holes in terra cotta and other clay pots. Using such tools prevent pots from breaking during the process when kept cool with some water for each attempt.
Keep in mind that pots made out of clay materials such as terra cotta and ceramic are more brittle than the good old sturdy plastic pot. So be very careful when doing this on your own.
Protective Gear and Tools
You may opt to use a working glove and safety goggles for added protection if you’ve never tried doing this before. I would also suggest having someone to either help or supervise you through this task.
Having said all that, creating a drainage hole or two in terra cotta pots can be done with ease and very little time with the right drill bit. Diamond drill bits sized from 0.25 inches to 1 inch (0.63–2.54 cm) typically do the trick.
How many holes are ideal? Which sizes are best? Check out our drainage hole guide!
4 Easy Steps
Using a diamond drill bit, add holes in the terra cotta pot by:
- Marking the area you want to drill into. This will help you aim correctly and create a clean hole.
- Keeping the area wet and cool. You can do so by placing the pot under running water from a faucet or hose. Aside from that, you can opt to simply pour some cool water after each attempt.
- Drilling at an angle. Start drilling at a slanted angle of about 30–45° to help create a notch in the area which will keep the drill in place. Then slowly straighten it out as you go. When done straight down, your drill will slip.
- Sanding off the drilled area. If you want to be extra careful, go on ahead and sand off the drainage hole so there are no sharp edges. Finally, rinse the drilled pot.
Pro Tip: Lay down a textured cloth, like a hand towel, and then place the pot upside down on it to prevent slipping and sliding.
This will generally work with concrete and glass containers as well.
FAQs
What plants can you grow in terra cotta pots with side holes?
Terra cotta pots with drainage holes only on the side are great for growing moisture-loving plants that don’t tolerate dry soil well. Others with drainage holes both at the bottom and on the sides can be great for plants such as cacti and succulents that prefer drier mediums. Pots with multiple big side holes or pockets are best for orchids or herbs.
Do terra cotta pots absorb water?
Not all terra cotta planters absorb water. Unglazed terra cotta pots are highly porous so they do wick away excess water from a moist growing medium. In contrast, glazed terra cottas don’t absorb water because of their waterproof coating generally which is added to prevent excessive water loss. They are also less likely to develop mold and mildew.
Can plants grow in pots without holes?
Plants can be grown in pots without any drainage holes as long as the owner closely monitors their watering needs. Otherwise, plants kept in growing containers without any holes are likely to develop root rot among other things. However, certain plants that thrive in swampy conditions, such as moss and ferns, can better handle such an environment.
Why do some plant pots not have holes?
At times, planters that don’t have holes are meant to be used as decorative containers or cache pots. They are usually used for double-potting both indoor and outdoor plants. Smaller regular plastic pots with holes at the bottom are typically fitted into larger colorful pots. Bricks or gravel may be placed between the two to ensure proper drainage.
Summary of Why Terra Cotta Pots Have Holes on the Side
Terra cotta pots with side holes are used for collecting water to form a reservoir, improving drainage to prevent wet soil, ensuring aeration to prevent anaerobic activity, promoting root development to grow more hardy plants, and increasing usable planting space.
When used incorrectly, terra cotta pots with side holes can be detrimental to plant growth as they can lead to waterlogged mediums, excessive water loss, messy water spills, and wasteful growing medium spills.
Sources
- “A Place to Take Root” by n/a in Botanic Garden of Smith College
- “Gardening in Containers” by y Henry Clay and Jeff Lewis in University of Georgia Extension
- “Tips for Growing Houseplants in Maine” by Donna Coffin, Rebecca Long, and Matt Wallhead in The University of Maine Cooperative Extension
- “Development and construction of an air-pruning propagation bench, and its proper use” by Julia Walker in University of Washington
- “Plants For Damp Or Wet Areas” by Karen Russ in Clemson Cooperative Extension
