How Long Can Cactus Go Without Water?

Ideally, a cactus plant can survive for two years without water. These plants have thick stems and a protective covering that prevents water loss. However, indoor cacti are a different ball game altogether because the conditions differ.

Let’s discuss the watering needs of a cactus plant in the USA and what you need to be careful of.

Can Cacti Survive Without Water?

Like any other plant, the cactus plant cannot live without water, which is necessary for photosynthesis. However, the cacti are adaptive plants capable of adjusting to their surroundings and surviving for months and even years without water.

According to the Arizona Sonora Desert Museum, most cactus plants develop succulence, which helps them live without water for extended periods.

Within their succulent stems, they can trap water that allows them to endure dry seasons. The idea that cactus plants can survive with little or no water is just a myth.

Cacti like drinking enough water to store it in their spongy stems. However, they also don’t like to sit on top of a wet substrate that may cause root rot.

Signs of an Underwatered Cactus Plant


Discoloration is one of the most common signs of underwatering. An underwatered cactus turns dark because of the rapid evaporation from its stems.

Sometimes, it turns yellow because of insufficient chlorophyll production resulting from less moisture supply.

It also happens because the dying roots experience extreme dryness. When testing for underwatering, be careful, as it could be a sign of overwatering or the lack of natural light.

If you suspect overwatering, check for mushiness. If the plant is soft in certain areas, it is overwatered.

Wilting Tips

A lack of water can also result in curly leaves. Because they can’t get enough water, they squeeze all the moisture left in their system to compensate for the shortfall.

The tips start wilting when water becomes unavailable for several days. The leaves also begin to turn brown and brittle.

Dead Brittle Roots

The best way to inspect for underwatering is to uproot the plant from the pot. The root that doesn’t get enough water will turn dead and dry.

These roots sometimes become so weak that they come off even at the slightest touch.

How to Fix an Underwatered Cactus

Bottom-Soaked Watering

For wrinkly cactus plants, bottom-soaked watering is a technique that always works. Here is what you must do.

  • Fill a container with tap water. Then, soak the shriveled cactus plant in the water. The flowering pot should have a hole at the bottom to suck up the water and soak the potting mix. Let your plant sit in this water for around 40 minutes. If the plant is severely dehydrated, you can leave it there for three days straight.
  • When the top soil is moist, remove the plant, and allow it to drain. After the water from the substrate has drained, place it back into its original position.

Within a few days, the shriveled cactus will become plump again.

Uproot the Plant and Trim the Dead Roots

While the bottom-soaked technique works nine times out of 10, there is always that 10th time. If it doesn’t work for you, try uprooting the plant.

Now, check the roots. If the roots are dying out, wash them thoroughly. There could also be a pest infestation in those roots.

Instead of using a packaged pesticide, you can make one of your own. Mix five tablespoons of dishwashing soap and three teaspoons of neem oil in one gallon of water.

Now apply the concoction to the infected root until the pests are gone. You can also use diluted isopropyl alcohol.

Lastly, trim and remove the dead roots, and re-pot in a fresh potting mix. Water adequately, and the Plant will resurrect itself.

Re-Pot the Plant

As discussed above, you must re-pot the plant after removing the dead roots. Also, use a fresh potting mix, as the previous mix would revive the infections.

Before planting your cactus in the fresh mix, allow the roots to air dry. After potting the cactus plant, don’t water it right away. Instead, allow it to sit in a cool shaded place in your home in the USA.

After a few days:

  1. Start giving small amounts of water to your cactus.
  2. Continue the practice for a week or two.
  3. Slowly increase the amount of water.

Prune the Dehydrated Cactus

Dead parts of the plant are least likely to live again. Therefore, you must prune them with a sharp knife.

Make sure the knife is perfectly sterilized. The slightest impurity on the cutting tools can infect the cactus plant, and these infections can spread quickly.

What Makes a Cactus Plant Survive in Arid Conditions

Shallow Roots

Shallow roots absorb water from their surroundings to keep the plant alive. These roots tend to expand to absorb ground or substrate water.

In dry conditions, these roots tend to retract, thus allowing the cactus to preserve as much water as possible. As a result, the cactus plant survives as long as it has water in its system.

Spongy Stem

After traveling through the roots, the water is stored in the spongy stem tissues. This stem is built of slimy mucilage cells. The stem inhibits evaporation and binds to the water.

As the stem absorbs water, its cells expand until they can’t hold more water. The stems are surrounded by little openings called stomata.

The stomata open at night to slow the evaporation process to compensate for the water loss during the day.


The sharp spines on your cactus plant retain enough water for the plant to survive in dry conditions.

These spins also limit airflow, thus preventing the sun’s rays from causing dehydration.

Moreover, these spines also protect the Plant against desert herbivores that enjoy munching on the juicy flesh of the cactus plant.

Thick Epidermis

Around the stem region, the cactus plant has a thick layer called the epidermis. Because of its waxy texture, the moisture cannot pass.

As a result, the cactus Plant retains the water it needs to survive. The epidermis also prevents exposure to pathogens, and they cannot pass through it.

How Long Can Cactus Plants Survive Without Water?

A cactus plant can survive for months and even years, depending on its ability to retain water. As we have discussed, a giant desert cactus can live for two years without water.

Most cactus plants are cylindrical, semi-cylindrical, or spherical. With an increase in size, the body volume increases compared to its surface area.

Therefore, a bigger cactus plant is more likely to retain water than a smaller plant. The seedlings are highly prone to drying because of dehydration.

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Final Word

A cactus plant can live for long durations without water, but like any other plant, it needs water to feed its thirsty stems.

Cacti have various adaptations which allow them to survive the arid conditions of the desert. They can retain water because of their spines, shallow roots, and thick stems.

While underwatering is unfavorable, overwatering is dangerous, as it causes root rot. Lastly, bigger cacti are more likely to survive because they store more water than smaller cacti.

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