Cactuses can be grown hydroponically. While they aren’t the most common kind of hydroponic plant to grow, they can be a unique touch to your hydroponic garden. Hydroponic cactuses thrive because you can give them all the light they need to mimic their natural environments. They’re also decently low maintenance, only needing fertilization twice a year.
Read on to learn how to grow this unique hydroponic plant that is sure to catch everyone’s attention!
Can cactus be grown hydroponically?
Cactus can absolutely be grown hydroponically! With the correct hydroponic system, nutrients, lighting, and attitude- you can grow any plants without soil.
There are two primary kinds of cactuses- forest cactuses and desert cactuses. The main ones that you see in stores are desert cactuses because of how hardy they are in most conditions.
Let’s talk more in depth about how to grow hydroponic cactus.
Varieties of Cactus Commonly Grown Hydroponically
Some common and unique varieties of cactus plants commonly grown hydroponically include:
- Fairy Castle Cactus
- Christmas Cactus
- Golden Barrel Cactus
- Feather Cactus
- Moon Cactus
Of course, you can grow any kind of cactus that you want to outside of these common varieties.
What Are The Benefits Of Growing Cactus Hydroponically?
Growing cactus hydroponically has many benefits, including brightening up a space, using less resources, the ability to grow many cactuses, and giving your cactuses the environment they need to truly thrive.
Let’s dive a little deeper into the benefits of growing these indoor plants hydroponically!
One major benefit is that it can really brighten up a space! Cactuses have a knack for cheering people up. Having a hydroponic garden full of cactuses can really be a focal point in a room.
Another benefit of growing cactus hydroponically is that it uses less resources than traditional gardens. Although cactuses already don’t use many resources, hydroponic gardens are even more efficient.
You can also grow many cactuses even if you have a small space or don’t live in a hot region.
Many people grow cactuses on windowsills, but they don’t get as much natural light as they need to truly thrive. You’ll be surprised at how big and happy your cactuses get when you grow them under the right conditions!
Which hydroponic system is best for cactuses?
The best hydroponic system for cactuses is Leca.
Since cactuses don’t need much water, traditional hydroponic systems don’t work very well for cactuses because of their near-constant water supply with the roots in water.
Leca is a great way to keep your cactuses happy without growing in soil. More on Leca later!
How to grow Hydroponic Cactus
Now let’s talk about the specific needs of growing hydroponic cactus.
Should you pick Seeds vs. Clones?
You should absolutely pick clones when growing hydroponic cactus, if not a cactus from the store that’s already grown a bit. Just be sure to carefully remove the traditional soil from the cactus roots.
You can grow cactuses from seed if you want to, but it would take between six months to a year for your cactus to even be ready to transplant into your Leca.
Planting medium for hydroponic cactus
Leca are expanded clay aggregate, aka baked clay balls. They’re fired in a rotary kiln at incredibly high temperatures. This results in a light weight expanded clay aggregate 5x its original size.
Leca produces happier plants and is safer to use if you clean it off thoroughly after buying it. The manufacturing process is still a bit of a mystery and it’s important to make sure there’s no leftover residue on your Leca.
First, rinse it off. Then soak it for a day with tap water. Finally, dump and refill the water and let it sit for another 24 hours.
If you’re using your Leca right away, there’s no need to dry or store it.
Hydroponic Cactus Nutrient Requirements
Cactuses only need to be fertilized once or twice a year during the spring and summer when they’re in their growing period.
They need more phosphorous compared to nitrogen, likely diluted at least by half.
Optimal pH
Different species of cactuses each have their own desired pH. That being said, they typically love acidic environments with a pH ranging from 5 to 7.
Light for hydroponic cactus
Hydroponic cactuses need between 10 and 14 hours of bright light in order to mimic their desert environments. HID lights are a good choice for hydroponic cactuses because of their intensity.
Harvesting Hydroponic cactus
You don’t necessarily “harvest” hydroponic cactuses. However, you can cut certain hydroponic cactuses in order to clone them.
Take a cutting of a hydroponic cactus by cutting about 3 inches of an actively growing stem. Be sure the cutting has one or two nodes.
Depending on the kind of cactus, you may be removing a thick pad instead.
No matter what, let the cutting sit for a few days to let the ends develop a callous before transplanting into your Leca.

FAQs
Can you grow a cactus in water?
You can grow a cactus hydroponically using Leca and water. Fertilize in the spring and summer with a half-strength hydroponic fertilizer.
Can you do hydroponics with succulents?
You can do hydroponics with succulents. Succulents grow best in Leca compared to other hydroponic systems. Succulents only need about six hours of light a day!
Can you grow Christmas cactus hydroponically?
You can grow Christmas cactus hydroponically. It is one of the most popular hydroponic cactuses to grow because of its beautiful, cascading blooms.
Conclusion
Clearly, hydroponic cactus are easy to grow and can be a beautiful addition to your hydroponic systems. While cactuses aren’t the first thing to come to mind when you think of hydroponics, they’re certainly worth it! With minimal effort you can have gorgeous cactuses in your garden.
If you want to learn about growing other unique hydroponic crops, check out the rest of our blog!