Table of Contents
- 1 How Long Can A Cactus Live Without Water?
- 2 How Often Should I Water Cactus?
- 3 How To Water Cactus
- 4 Can You Overwater Cactus?
- 5 Factors To Consider When Watering Cactus
- 5.1 What Species Of Cactus Is It?
- 5.2 Is Your Cactus Small Or Large?
- 5.3 How Much Light Does The Plant Receive?
- 5.4 Are You Using Proper Container Size Or Type For A Cactus?
- 5.5 Are You Using Proper Planting Mix For Cacti Plants Indoors?
- 5.6 At What Temperature Is Your Cactus Kept?
- 5.7 How Humid Is The Air?
- 6 FAQ
- 7 References
Have you ever wondered how to water a cactus? Most people are at a loss as to how often you should water a cactus.
Since they are known to survive in the desert. In this post, you’ll find out how often you should water cacti both indoors and outdoors, as well as the other basics of watering them.
Cactus plants are one of the most wanted plants, especially for beginners in house planting since they are really easy to take care of.
If you’re a busy person, you might want to have this low-maintenance plant too because you don’t need to fret about watering it every day.
However, this fact is also the reason why most new cactus owners and even some long-time owners have trouble with how often they should really water their plants.
So, how often do you water a cactus?
In the simplest sense, you only need to water your cactus when its soil is completely dry. As stated above, cactus need to be watered at least once a week.
In fact, some varieties can even survive for as long as two years without water. The appearance of your cactus as well as its potting mix dryness are good indicators if you want to know when and how often it needs water.
Of course, there are also a few things to consider if you want to know how often to water cactus.
All cacti have different needs, but it mostly varies on your cactus’ size as well as the size of your pot, the climate and temperature in your area, and the current season.
Read on to find out more about your cactus watering needs.
How Long Can A Cactus Live Without Water?
No matter how hardy these plants are, they can’t live without water forever. Cactus plants are living beings and they require water to live.
It’s just that cactus can survive without it for an extended period of time. In fact, some cactus species can go for two years without water.
Cactus use the water that they store in the stems and roots much more efficiently compared to other plants. Furthermore, it doesn’t give up its water through evaporation as easily as other plants since it has no leaves.
If the cactus is in the ground, you might it would have deep roots to acquire more water supply.
In reality, cacti often have shallow and extensive root systems that stay just beneath the ground and can extend a few meters from the cactus, ready to collect as much water as possible.
The plant releases more roots once the rain comes and will shrivel back up and break in the drier seasons to help save its water supply.
How long a cactus can survive without water can also depend on the species of cactus, its size, and the location where it is growing.
The mammillaria species, as well as other smaller cactus species, can live without problems during the whole winter without water, more or less about four months while they are stored near freezing temperatures, a couple of degrees higher during sunny days.
Related post: 18 Different Types of Mammillaria Cactus Plants
The bigger species, such as the Barrel cactus or Ferocactus types, can last longer without water for an extended period of time since they can be very big. Therefore, they have bigger water storage.
How Often Should I Water Cactus?
It is a known fact that cacti are tough plants that can survive in extreme climates. Their stems and roots act as water storage that will help them survive during an extended drought.
However, it doesn’t mean that you should let them go for longer just because of this. Yes, they will survive but they won’t grow to their potential and they certainly won’t thrive.
Related post: How Fast Do Cactus Really Grow?
If your cactus is currently going through its growing season, you need to increase the times in which you water them.
A cactus’ growing season is usually in the warmer months or from spring to fall. From March to October, you need to water your cactus once a week or once every ten days.
On the other hand, during the colder months or from October to March, your cactus is past its growing season. You only need to water them once to twice a month.
How Often Should I Water My Cactus In Winter?
As stated before, treat winter as the resting season for your cactus. If your cactus is in a dormant period, you need to water them even less than usual.
For instance, a safe estimate is to water them once every four to six weeks, or just once a month. If the cactus that you have is native to the jungle, it’s fine if you add a bit of mist here and then every winter.
Basically, your cactus just needs enough water to get through winter. If you mostly have cacti that are native to arid areas, take extra care since they don’t adapt well to cold, dry winters.
How To Water Cactus
There are different ways that you can water your cactus. If your plant is placed in a pot.
- Place the pot in a saucer with water.
- Let the roots of the cactus absorb moisture.
- Once you think that the soil is wet halfway up, take it away from the saucer.
Some prefer to water their cactus by submerging them completely in water. Most of the time, this method is applicable to cacti that have big and thick roots.
This next method of watering is much simpler. You only need to apply water to the surface of the soil.
The amount of water that you use in this method should depend on the area where your cactus is placed, as well as the heat and sunlight. Let the water drip down the drainage holes.
No matter what method you choose for watering your cactus. Always remember not to overwater them. Also, remember the type of cactus that you have to guide you in watering.
What Kind Of Water Should I Use In Watering Cactus?
In general, your cactus is not picky when it comes to water. In fact, tap water works just fine but if you happen to collect rainwater, it is much more preferable.
This is because some tap water has varying quantities of dissolved minerals that can be harmful to your plant.
Other tap water has chemicals such as chlorine and fluoride too. These components can cause some build-up on your plant’s soil and roots that can block the necessary nutrients that your cactus should be getting.
How To Tell When It’s Time To Water Your Cactus
So, you get the idea not to water your plant too regularly. Then, how would you know when to water your cactus?
As an owner, you should know when your plant is in distress. If your cactus is in dire need of water, you might notice a slight discoloration in its overall appearance.
Signs Of An Underwatered Cactus
Most of the time, your cactus will look brown and dry. It would also shrink, shrivel, and pucker if it’s underwater.
You don’t need to wait for visible signs of an under-watered cactus before you actually water them. To know the optimal time when to water your cactus, check these steps:
- Thrust your finger in one or all of the drainage holes in your cactus container. If you can still feel some moisture, you don’t need to water your cactus. Just wait for a few more days or weeks.
- Insert a small skewer or stick through the bottom of the potting mix gently, then wait for a couple of seconds before pulling it out. Feel the stick if it looks damp or if there is still visible moist soil sticking on it. If it is, wait for a couple of days before watering.
- Push your finger on the potting mix at the top for a couple of inches in. If the mix and soil feel dry, then it is time to water it. As long as the soil is wet and damp, with a few potting mix that still sticks on your fingers, your cactus will be just fine if you hold off watering.
Basically, what you’re looking for is a dry soil before water. Don’t just look at the top or bottom of the soil or potting mix; check for wet spots on the inside too, since it can still be wet.
Can You Overwater Cactus?
Let’s discuss the other extreme. If you’re still a newbie and you’ve found out that cactus need water too, you may overcompensate and water them more than what’s necessary.
Believe it or not, it is better to under-water your cactus compared to overwatering them.
It’s harder to turn back from overwatering a cactus since most of the time, it will lead to rotting. Remember that they store water on their own, so you don’t need to fuss about watering them constantly.
Signs of an Overwatered Cactus
It can be quite tricky to spot an overwatered cactus because if you look outside, your cactus might look really plump and healthy.
In fact, they can even show new growth. You won’t notice that the problem is at the roots. If your cactus is overwatered, the roots will surely rot, and it can be hard to revive them.
In some instances, overwatered cactus can show brown spots on the outside. They might also look mushy if they have too much water.
On some cactus-like saguaro and barrels. You might notice that the seam that connects the ribs on your cactus will start to split open when they are given too much water.
In time, the scab or split will explode, especially in the summer. On the other hand, you can also have some freezing problems with your overwatered cactus in the winter.
How To Save An Overwatered Cactus?
If the rotting is not yet deep and hasn’t affected the cactus entirely, there might still be a chance to revive them.
- Remove the cactus from the pot if ever you suspect that it’s overwatered. Use a few newspapers to wrap around the cactus then tip it out.
- Gently comb out the roots to remove as much soil as possible then check if there are black or brown parts on the roots. You can still salvage the plant if most root parts are still white.
- Trim and remove any black or brown roots. If the affected areas are not that extensive, they can still recover.
- After you’ve removed the affected roots from the healthy ones.
- Repot and let the cactus reroot in another pot that has good drainage.
Be sure to remove any rotting parts to make way for the regeneration of a whole plant. Furthermore, the rot may spread if you don’t remove them.
Before repotting the cactus, make sure to let it heal and dry in a dry area for a few days.
Factors To Consider When Watering Cactus
There are also a few things that you need to consider when determining how often you need to water your cactus. You can use these factors as your guide to watering them.
What Species Of Cactus Is It?
Yes, all cacti need less watering than normal plants. However, you can divide the cactus into two types, where one needs more watering than the other.
Cactus can be native in arid areas or in the jungle, and the watering differs in both.
Related post: Types of Cactus Plants: What Kind Do You Have?
These are the types that are native to the desert. It means that they thrive in dry and hot areas even without a regular water supply. This cactus type doesn’t need too much watering but will still survive.
From March through September, or during the growing season of the cactus, your plant is in the process of growing.
Your cactus needs more frequent watering at this time compared to when it’s dormant during winter.
Examples: Golden Barrel Cactus (Echinocactus grusonii), Prickly Pear Cacti (Opuntia species), Column Cactus (Cereus uruguayanus)
The jungle is wildly different compared to the desert. The cactus that are native in this area are used to the humid conditions of the jungle rain forest. Most of the time, these types live over the canopies of trees or under shade.
Although they are also hardy, jungle cactus doesn’t like it when they are left to dry completely, especially during their growing season in spring and summer.
However, this doesn’t mean that you should leave them with constant watering or they’ll rot.
You can just mist them a few times per week. You can resume watering them once a week when they are dormant in the winter.
Some examples are: Orchid Cactus (Epiphyllum spp.), Easter Cactus (Rhipsalidopsis spp.), Thanksgiving Cacti (Schlumbergera truncate), Christmas Cacti (Schlumbergera x bridgesii)
Related post: Various Types of Holiday Cactus Plants
As discussed above, there are seasons when your plant is growing more actively.
During the summer, you need to water your cactus more frequently, not only because it’s hot and water evaporates faster during this season, but because your cactus is also busy growing, so be sure to give them more water.
During cooler months or winter, your plants go dormant, so treat them like they’re resting and decrease the frequency of your watering habits by half or more. They don’t need the extra water when they are dormant.
Is Your Cactus Small Or Large?
It doesn’t necessarily mean that if you have a bigger cactus, you need to water them more often. In fact, bigger cactus means that water evaporates less from the surface.
What bigger cacti need is more water because of their size but the frequency should be less compared to smaller ones.
What you need to water more frequently are younger and smaller cacti, especially when they are growing in pots to promote higher growth rates.
How Much Light Does The Plant Receive?
If your cactus is in constant direct sunlight, you might need to water them more frequently.
This is because the heat from the sun lets water evaporate faster, and the sunlight can also let the soil where your cactus is planted dry more quickly.
If they are indoors, your plants that are near windows facing the south might need some water more.
Cactus that are positioned near the north part of the house, where it is comparably cooler, don’t need much watering.
Are You Using Proper Container Size Or Type For A Cactus?
If your cactus is in a bigger pot, it will take a while for the water to completely dry out or evaporate.
Your plants can also take much more time to absorb the water in a bigger pot. A safe bet is to water cactus in bigger pots every four to six weeks.
Smaller cacti in smaller pots need water too, but not too much. What they need is more frequency since your plant can easily absorb it.
It is a given that water in smaller pots dries more quickly than in bigger pots. Most cacti love it when they are in smaller containers. In addition to this, it is easier to keep your cactus from rotting if they are in smaller pots.
It is also important to take note of the pot that you use. There is more moisture buildup if you use plastic pots.
This makes the soil take a longer time to completely dry. Just like with succulents, it is ideal to have your cactus in terracotta pots.
Related post: Are Cactus And Succulents the Same?
Since these pots are porous, water can pass through easily and it provides more breathability.
Whatever type of pot you use, you also have to make sure that it has a lot of drainage holes. What you need to prevent is rotting. If your pot has no holes, then you’ll surely have this problem.
Finally, note that cacti that are planted in pots need more water compared to the ones that are directly planted in the ground.
Are You Using Proper Planting Mix For Cacti Plants Indoors?
The potting soil is important too since it will determine how fast or how slow the water can pass through or be absorbed by both the soil itself and your plant.
What you should look for is any medium that drains fast. Most of the time, the common cactus mix is enough for your cactus, but you can also make your own by combining perlite, coarse sand, and potting soil.
If you have a good draining mix, you can prevent rot since water can be easily drained as long as you don’t drown your cactus. This also means that you have to water them more frequently.
At What Temperature Is Your Cactus Kept?
Just like light, you need to water more if the temperature is high. High temperatures mean that the water evaporates faster than usual.
Most of the time, it is also when your plant grows more proactively, thus needing more water. Make sure to monitor the dryness of the soil constantly during higher temperatures.
At lower temperatures or during winter, your cactus enters dormancy. You can just leave them be and they’ll be fine even if you just water them every four to six weeks.
Furthermore, you should also take note of the airflow around your cactus. More airflow also facilitates faster water evaporation.
If you place them near or on highly ventilated areas, make sure to constantly check on your cactus too because they might need more water.
How Humid Is The Air?
Even if most cacti like arid environments, they can also thrive if you leave them in the perfect humidity level.
When a cactus is placed indoors, you must check for the humidity especially if the type of cactus that you have is native to arid areas.
In general, you can water less if the area where you planted your cactus is more humid. To be sure, always check if the soil is dry, even if indoors.
It’s okay to mist cactus, especially if you have the ones that are native to the jungle. On the other hand, you must not miss your cactus, especially the desert cactus.
They are not used to surface moisture, unlike the jungle types. They usually get the moisture that they need from their roots.
On the contrary, some plant owners believe that you should not mist cacti since there’s a huge possibility of overwatering them.
Furthermore, they also believe it is quite useless to mist cactus since they don’t absorb water from their bodies.
A good practice is to watch for your cactus’ reaction to misting and also check for the type you have.
It’s a bit tricky since Christmas cactus loves a bit of misting daily. Either way, they can go with or without it, depending on your choice.
How often should I water my indoor cactus?
During the spring and summer seasons, an indoor-grown cactus plant will require watering every 10 days or longer. During the wintertime, cactus plants require watering every four to six weeks.
Can I Mist Cactus Plants?
Yes, you can mist cacti, particularly those native to a jungle environment. For example, the Christmas cactus is a perfect example of a cactus that can take misting on a daily basis. However, do not mist cactus that is native to desert cactus (i.e. arid cactus types). Unlike jungle types, desert cacti don’t like surface moisture, rather they survive by water being absorbed by their roots.
How much water should a cactus Get?
You must become accustomed to inspecting the dirt to see whether your cacti are thirsty. Generally speaking, a healthy cactus will need to be watered every one to two weeks during the growing season. During the dormant season, the frequency of visits changes every three to four weeks.
How do you know when a cactus needs water?
The simplest method to find out whether a cactus needs water is to place a finger into the top inch of the soil. If you feel the soil is moist, wet, or damp, do not water the soil. Wait for a day or two before checking again.
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.