When you think of cactus plants, you probably picture a plant alone in the desert with spikes on it.
This is one of many kinds of cactus plants.
They are part of the succulent family and so, they have the ability to store water in their stem, roots, and leaves.
They are low-maintenance plants, but they are not known to be fast growers. So, you might wonder, how fast will my cactus plant grow? And how can I make them grow faster?
So, how fast do cactus grow?
Most cacti grow slowly to moderately, In the early stages of growth, it might take them 2 or 3 years to grow just a couple centimeters.
But when cactus plants are established, they grow 1-3 cm in height each year. There are some fast-growing species like Harrisia pomanensis and pereskiopsis that may grow over 10-15 cm in just one year.
If you want to grow a cactus to its full size, it may take many years. Keep reading to learn exactly how long it takes for cactus plant growth, what you might be doing to impede that growth, and what you can do to make your cactus grow faster.
Table of Contents
How Fast Do cactus Grow?
Let’s discuss the various growth stages of cactus plants because, just like most plants, they need to start as seeds.
Germination
It takes several weeks, sometimes even several months, for the germination process to occur in seedlings. You may notice spines growing within a month, but don’t forget that not all cacti have spines.
If you don’t see anything sprouting after a month, just keep waiting. To help the process along, cover the cactus overnight, but uncover it during the day to let it breathe. Water the plant every time the soil gets dry.
Seedling Stage
Once your cactus plant eventually sprouts to the size of a marble, you should remove it from the propagation tray into its own pot. It is not uncommon for it to stay this size for 12 months.
Seedling Stage
Depending on the cactus plant you have, the growth rate will vary. As mentioned above, it is typical for an adult cactus to grow 1-3 cm each year.
Why Are Cacti Slow Growers?
Many people choose to start their indoor gardening adventures with cacti and other succulent plants because they are, frankly, hard to kill.
The lifespan of cacti ranges from 10-200 years and there are over 1500 different species of cacti. What most of them have in common is their slow growth rate. [1]
There are a few reasons from their plant history that have led them to their life of slowly inching bigger.
Soil And Climate
When we think about where cacti come from, slow growth is part of their survival. They come from desert climates where it scarcely rains and nutrients are lacking.
All plants need these things in order to perform the process of photosynthesis. The fact that they are lacking in both of these essential plant needs means that they can’t grow very much and can’t grow very fast.
In fact, cacti have evolved to focus on what resources they do have for survival instead of fast and large growth.
Their unique ability to conserve water and other resources in their stems and foliage means that they can survive long periods of time without water and through extreme heat.
They Have No Leaves
You have probably noticed that cactus plants don’t have leaves. They have evolved this way because plants typically transpire through their leaves, meaning that the water absorbed by a plant’s roots is evaporated through its leaves.
If cactus plants did in fact have leaves, it would make them even harder to grow because of the heat and lack of water in the desert!
But, because they don’t have leaves, it makes it harder for them to soak up the rays of the sun. So, that means that it is even harder to create energy through photosynthesis.
When plants have large leaves, they have more chlorophyll which is a vital component in photosynthesis.
Cacti have less chlorophyll than other plants and therefore limit their ability to create plant food from the sun and use it to grow.
What’s more, some cactus species have spines and wool on their stems that shade them from the sun which makes it even harder to soak up the rays!
They Have Fewer Stomata
Another reason that cacti have a slow growth rate is their stomata. If you aren’t familiar with what stomata are, they are pores located on the surface of all plants that help them take in carbon dioxide and, in turn, carry out photosynthesis.
Whenever plants open their stomata pores, carbon dioxide rushes in and some water evaporates from the plant. For any plant to grow quickly, it needs to take in a lot of carbon dioxide.
Since cacti need to retain as much water as possible, they evolved to have fewer stomata than other plants.
Therefore, they can’t take in as much carbon dioxide which limits their ability to perform photosynthesis.
In desert conditions, survival and water retention are much more important than gaining energy for fast growth.
Am I Impeding Their Growth?
While cacti are fairly resilient and easy-to-please plants, there are a few reasons why your plant might not be growing very much at all.
Not Using Proper Container
First, leaving it in a container that is too small can limit the nutrients that your cactus plant can acquire. If you don’t give your cactus an appropriate pot, it might die, and if it doesn’t, it will certainly stop growing.
Don’t Move Too Often
Second, moving it around regularly can stress it out. When you repot your cacti, let it get used to the new environment for a few days before putting it back in direct sunlight.
This will give your plant’s roots a chance to latch on and get accustomed to the new space.
Overwatering Your Cactus
Third, watering too much can be dangerous. Remember that cactus plants are used to retain water. In fact, they are built to retain water.
When you water it too much, this can increase the chances of root rot significantly.
Unfortunately, if you start to overwater your cactus, it might not look like it is affected right away, and it may even start to grow a bit bigger.
But then, suddenly, the roots will rot and the cactus will die. The really sad part is, once you start to overwater your cactus it is not easy to save it at all.
Keeping Your Cactus Covered For Too Long
Finally, if you keep your cactus plant covered for too long, this can decrease the growth rate. In general, it is smart to cover cactus seedlings during germination to increase humidity and keep the baby cacti warm. This will increase their chances of germinating.
But, if you don’t remove the cover when the seedling starts to grow, you are preventing necessary ventilation from occurring. This can stunt growth and potentially kill the cactus.
How To Make A Cactus Grow Faster
If you are not responsible for doing any of the impeded growth actions from the last section and you want your cactus to grow faster, here are a couple of tips to help you.
Get The Right Container
Always give your cactus a container that is slightly bigger than you think it requires. This will give it more than enough room to grow. The roots will be able to stretch out farther and better able to stabilize a larger plant.
Get Well-Draining Succulent Soil
Because cacti retain their water and don’t need that much water to begin with, it is easy to overwater them. Potting them in well-draining soil will help reduce the risk of overwatering and root rot.
Give It Lots Of Sun
Remember that cacti originated in desert environments where the sun shines bright. They need lots of sunlight.
Try to find the brightest spot in your home for the plant and turn it every week so that the entire plant gets sunlight. The more sunlight it gets, the better they are able to perform photosynthesis.
Maintain The Optimal Temperature
Cacti that are grown indoors thrive in temperatures between 65-80 degrees Fahrenheit. Keep these temperatures as consistent as possible.
Use Succulent Fertilizer
Using a fertilizer can give your cactus plant the boost it needs to grow faster. If you decide to give it some fertilizer, make sure that it is liquid and low-nitrogen.
Conclusion
In general, you won’t be seeing any shooting growth with your cactus plants. You can’t change their biology and evolutionary history that got them where they are today.
You can help to make it happy and healthy which will help it to grow and maybe grow a little faster. Make sure you are doing everything you can to give it what it needs and it will reward you.
If you aren’t willing to wait and watch for the slow growth of your cactus, there are a few species that grow faster than others, including Cereus, Trichocereus, and pilosocerus cacti.
Even if they don’t grow fast, though, you have to admit that they are pretty unique, beautiful, and easy to maintain plants to complement your home.
Lindsey Hyland grew up in Arizona where she studied at the University of Arizona’s Controlled Environment Agriculture Center. She continued her gardening education by working on organic farms in both rural and urban settings. She started UrbanOrganicYield.com to share gardening tips and tactics. She’s happy to talk about succulents and houseplants or vegetables and herbs – or just about anything in a backyard garden or hydroponics garden.