Cacti are incredibly hardy and easy to maintain as houseplants. One important requirement is to repot your cactus every 2 to 3 years or when it outgrows its pot. You can tell from the protruding roots through the drainage holes at the bottom of the planter or generally the poor health of the plant.
Over time, cactus soil gets degraded and repotting is the best way to replenish the nutrients. If the cactus is leaning on one side or falling over, inspect for root rot and remove all the damaged tissues before you plant it into a fresh soil mix.
Since most cacti plants are covered in spines and it can be difficult to handle them when repotting or transplanting. In this guide, I have a clear explanation of how to safely repot a cactus without hurting yourself or the plant.
What you need when repotting a cactus
To repot a cactus, you’ll first need the right tools and materials. Make sure you have the following:
Larger pot or container
If your cactus is root bound, you’ll need a slightly larger pot. Get a pot or container that is 2” larger than the one your cactus is currently sitting in. Don’t use a pot that is too big since it can retain excess water and lead to root rot and other fungal problems.
Additionally, the new pot must have drainage holes at the bottom. I always use unglazed terracotta pots when repotting my cactus and succulents. Apart from the normal drainage holes, their membranous walls allow air and moisture to pass through allowing roots to breathe.
Well-draining potting mix
Cacti are prone to root rot when overwatered or grown in waterlogged soils. They prefer well-drained growing media. When repotting, you need to use cactus or succulent mix which is designed to drain sharply but without losing nutrients.
You can also make your own cactus soil by mixing standard potting soil, coarse, and pumice. The addition of organic matter to this mix helps provide nutrients as the cactus grows. Don’t forget to test the pH of the soil, most cacti grow well in slightly acidic soil with pH levels between 5 and 7.
Cacti covered in spines are difficult to transplant. While these spines are not toxic or poisonous to humans or pets they can cause excruciating pain when they pierce into the flesh or skin. Leaving them deep into the tissues can also attract bacterial infections.
So, if you are planning to repot your thorny cactus, get ready with thick leather protective gloves. Additionally, keep pets and kids away from the working area.
How to repot a cactus – steps
Repotting or transplanting a cactus must be done during the active growth season. Spring and summer are generally the best time to repot a cactus so that the plant can establish itself before the cool winter. The plant should also be healthy before it’s moved to a new soil or pot.
Once you have all the required assortments, wear your protective gloves and long sleeves and proceed to repot the cactus as follows:
- Carefully remove the cactus from its current pot. Turn the pot upside down and gently tap the bottom to loosen the soil then pull the cactus gently out of the pot. A larger cactus plant may need at least two people to lift it safely from the pot.
- Loosen the root ball to remove excess soil and check the roots for any signs of pests or rot. Damaged roots are dark and mushy indicating a fungal rot.
- If the cactus has damaged roots, trim them off with a clean, sharp knife or pruning shears. Let the plant dry out for two or three days before repotting it. Skip this step if your cactus roots are strong and healthy.
- Place a layer of stones at the bottom of the new pot and then position the cactus in the center of the pot. Fill in the gaps with soil, gently pressing it down around the cactus.
- Don’t water the cactus again for two to three days to make it adjust to its new home. Then give the cactus a good watering, allowing the water to drain out of the bottom of the pot.
- After repotting, place the cactus in a bright, sunny location, but avoid direct sunlight. Water the cactus sparingly, only when the soil is completely dry.
Transplant shock can stress out a repotted cactus, so it’s important to provide good care for a quick recovery. Keep an eye on pests and diseases, avoid fertilizing, and don’t overwater the cactus. It can take several weeks or even months for a cactus to fully recover and establish itself in the new soil.
Tip: Make sure that you place the freshly repotted cactus back in its original location preferably facing the same direction. I always mark the side that is facing north with chalk or tape for ease of placement.
Repotting a cactus is highly recommended after every two to three years or when it’s excessively root bound. Make sure to use a well-draining soil mix and a slightly bigger pot with drainage holes at the bottom. Wear protective gloves to avoid injury from prickly cactuses.
“Growing cactus,” Texas A&M University
“Cactus Care in your Home,” University of California
Transplanting a cactus: The University of Arizona
My name is Diane M Lewik, and I am the founder of this website. I am a degree holder in plant biology from the University of California – Berkeley. Over years, I have cultivated a vast collection of succulents and I have learned a great deal about how to grow and care for these unique plants.