Why Is My Indoor Cactus Dying? 8 Reasons and Their Solutions

People love to buy cacti and succulents as indoor plants for many reasons.

For starters, they are drought tolerant, which means they will forgive you if you forget to water them for a few days or weeks.

Oh, and not to mention, the stunning array of colors and patterns that cactus is available in is enough to steal the hearts of many plant lovers.

However, the difficulty arises when your indoor cactus suddenly shows signs of distress.

It can often be difficult to realize why your plant is headed toward an untimely end.

So, Why Is My Indoor Cactus Dying?

There may be many reasons why your cactus is showing signs of distress.

Before you ask “how to save a dying cactus,” you need to understand how your cactus is dying. Is it turning soft and mushy, or is it rotting from the bottom?

Check your cactus carefully from the tips to the bottom of the plant.

It is necessary to treat your plant while it still has some healthy growth left and bring it back to its former glory.

Many reasons can contribute to the sudden death of your cactus.

These include overwatering, underwatering, pest infestation, inadequate or too much sunlight, fungal infection, root rot, and stem rot.

7 Major Dying Cactus Signs

Here are some tell-tale signs you must look out for to identify if your cactus is dying.

1. The Cactus Begins to Wither and Shrink

Cactus retain water in their fleshy stems, which is why these plants appear firm and plump.

A withered appearance is the most important indication of a dying cactus.

2. The Cactus Is Losing Its Color

If your cactus is dramatically changing its color, it is time to look for reasons for its distress.

A cactus loses its bright green pigment and turns yellow or brown for many reasons.

An underwatered, sunburnt, overwatered cactus or a pest infestation can lead to changes in the color and appearance of the cactus pads.

3. The Cactus Is Not Showing Any Signs of Growth

Not every plant shows a significant growth in height in a short time.

But if you have had your indoor cactus for a while and it is not getting bigger, it is a sign that something is wrong with your plant.

4. The Brittle Stem of the Cactus and Dried-Up Soil

Dry soil indicates that your cactus is dehydrated and needs water.

A dehydrated cactus starts showing wrinkled or shriveled pads, and the stem becomes brittle.

5. Black or White Patches Start Appearing on the Cactus Pads

Black, white, or green patches on your cactus indicate mold or fungal infection.

Cactus are sensitive to pests and fungus, so you must immediately treat the plant before the damage spirals out of control.

6. Blackish-Brown Spots Start Appearing on the Cactus

Blackish-brown spots on your cactus indicate root rot, a problem resulting from overwatering and inadequate light.

You must immediately treat root rot as it infects your plant’s roots first, causing the immediate death of the cactus.

7. The Cactus Starts Giving off a Foul Odor

Root rot or stem rot leads to the soft and mushy flesh of the cactus. The wet patches of the rotten plants will give off a foul smell.

How to Save a Dying Cactus: 8 Reasons and Their Quick Solutions

Three major growing factors govern the proper growth and health of a plant.

  • Watering schedule
  • Light
  • Temperature.

To revive a dying cactus, you must monitor the changes in these primary factors. Here are 10 quick solutions to save your cactus from an early demise.

1. Stop Overwatering Your Cactus

Cactus have water-storing abilities, so overwatering can severely damage your plant.

  • An indoor cactus needs watering after every 10 days.
  • A cactus requires even less watering during wintertime.
  • An overwatered cactus is soft and mushy.
  • Lower the amount of water you are giving to your plant.
  • Take your cactus out of its pot and repot it with a fresh mix.
  • Allow the cactus soil to dry out before you water it again.

2. Save an Underwatered Cactus

An underwatered cactus look shriveled and wilted.

However, it is essential to check the soil moisture level before you decide that the reason for your dying cactus is under-watering.

  • If your cactus is dehydrated, give it water!
  • Check if the soil is completely dry before watering your plant to prevent root rot.
  • Cut off the dead spines of the cactus.
  • Place the cactus in a pot of water since the plant absorbs water from the bottom of the soil.
  • Monitor if your cactus is losing its limp appearance after a few days.
  • If not, then look out for other signs of distress.
  • In South America, temperatures can spike up to 80°F on hot summer days, so your cactus will require water more than 2 to 3 times per week.

3. Pests Infestation

Mealybugs and other aphids commonly invade your cactus and suck the plant sap, leading to a lifeless appearance.

  • Identify and treat the pest’s infestation before it grows uncontrollably and causes your plant’s early demise.
  • Apply a spot treatment with a cotton swab dipped in concentrated rubbing alcohol, or spray a diluted solution of alcohol all over your plant.

4. Inadequate Light

The cactus shows signs of stress due to inadequate light in the form of stunted growth and discolored pads.

  • A cactus is highly susceptible to root rot when you give it too much water and too less sunlight.
  • Move your cactus to a bright spot in your room, for example, on a windowsill.
  • Fluorescent bulbs are an excellent option to provide artificial light to your cactus.

5. Sunburnt Cacti

Succulents are also susceptible to the sun’s scorching rays and can dry out very quickly.

Save your plant from an early demise when it shows the early signs of yellowing stems.

  • An extremely sunburned cactus will turn white and soft when it is highly exposed to sunlight.
  • Get your indoor cactus to a shady spot for a few days, and then moisten its soil if it is dry.
  • Limit sunburn by avoiding sprinkling water on the plant when placed in direct sunlight.

6. Cactus Fungus

Cactus are susceptible to fungal infections, which lead to the development of black spots, decay, and discoloration of the plant.

  • Remove the infected parts of the cactus so that the infection doesn’t spread to the whole plant.
  • Sterilized razor blades or knives can be used to scrape the damaged parts of the plants.
  • Stop overwatering your cactus; if it is not receiving adequate sunlight, place your plant in a bright spot.
  • Use fungicides available at your local gardening shops and treat your plant with the fungus control mixtures to prevent further infection.

7. Root Rot

The most common reason for root rot is overwatering and poor soil draining.

  • The condition is almost irreversible if you fail to recognize root rot and the cactus starts rotting from the bottom up.
  • However, you can cut off healthy stems and propagate those cuttings in a fresh cactus mix.
  • Create a proper draining environment for your cactus plant and monitor your watering schedule.

8. Stem Rot

Root rot progresses to stem rot, resulting in the loss of the vibrant green color of the cactus.

  • A cactus suffering from stem rot will show brown lesions on its stems.
  • The cactus wilts and flowering stop and the plant gives off a foul smell.
  • Stem rot can kill a cactus in less than a few days, and the condition is mostly impossible to reverse.
  • Take a look at the roots of your cactus.
  • If the roots are slimy and brown, remove the plant from the pot, and trim off diseased roots.
  • Repot the cactus with fresh potting mix, and allow the plant to recover from the damage for almost 7 to 14 days.

Why Is My Cactus Dying From Bottom

A cactus rotting or dying from the bottom indicates that its roots are rotten.

While the root infection hasn’t spread to the rest of the plant, you can cut off your cactus’s healthy green stem pieces and try to propagate the cuttings.

Prune off layers of your cactus, allowing the rot to get thinner until there are no signs of soft, brown, and mushy material.

Allow the cuttings to dry over a few days until the wound callus is over.

You can dip the stem cuttings in rooting hormone and then place them in a fresh cactus mix. Avoid watering until you see new growth on the cuttings.

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If your cactus looks sickly and withered, instead of assuming it’s dead, try to identify the root problem and help it fend off possible causes of its distress.

There are many reasons why your indoor cactus is dying. Luckily, with appropriate measures and care in the future, your plant can come back to life only after a few weeks or months.