Needle Cactus Turning White

Are you worried about your beloved needle cactus and noticing that it is not as healthy and vibrant as it used to be? Perhaps it is losing its charm and turning white? If so, do not panic!

There can be many reasons your needle cactus is turning white such as overfeeding, sunburn, and overwatering.

 In this blog post, we’ll explore eight reasons why your needle cactus is turning white and what you can do to save your cactus garden from turning white. From environmental factors to pests and diseases, we’ll cover everything you need to know to keep your needle cactus healthy and thriving.

So grab your gardening gloves, and let’s dive in!

1. Root Rot

Like many other plants, cactus plants are also prone to root rot. This condition occurs when the plants are excessively watered and are exposed to too much moisture, leading to root decay and, eventually, the death of the plant.

Root rot can be a reason why your needle cactus is turning white.

To save your needle cactus from root rot, follow the following tips;

  • First, stop watering the plant until the soil dries out completely. Overwatering is the most common cause of root rot, and giving the plant time to dry out is crucial.
  • Check the soil for moisture and signs of fungal growth. If the soil is still wet, remove the plant from the pot and gently remove the soil from the roots.
  • Trim off any mushy or blackened roots using a sterilized pair of scissors or pruning shears. Cut until you see healthy, white roots.
  • After trimming, repot the plant in fresh, well-draining soil. Use a pot with a drainage hole to prevent overwatering.
  • Cactus plants do not require a lot of water, so keep the plant dry.

2. Incorrect Soil

Although cactus plants are hardy and can survive in tough soil conditions, using the wrong type of soil can be one of the reasons why your needle cactus is turning white.

Using the wrong type of soil or too dense or compacted soil can prevent proper drainage, leading to root rot and eventual plant death.

To prevent your needle cactus from turning white, make sure you follow the following tips when ensuring the health of the soil;

  • Needle cactus thrives in well-draining soil, allowing excess water to drain quickly. A good soil mix for needle cactus combines gritty sand, perlite, and cactus soil mix.
  • Adding coarse sand or perlite to the soil mix can improve drainage and prevent water from pooling around the roots.
  • Avoid organic matter like coarse sand or perlite in the soil mix.
  • Needle cactus has a shallow root system and prefers a shallow pot. A pot that is too deep can retain too much moisture, leading to root rot.
  • Ensure the soil is not wet to the touch and is soggy.

3. Lack of Sunlight

Cactus plants are desert plants and thrive in loads and loads of sunlight.

Lack of sunlight can also be a reason why your needle cactus is turning white. Needle cactus requires bright, direct sunlight to thrive and maintain their vibrant green color.

If you want to ensure your plant receives the right amount of light, keep the following tips in mind.

  • Place the plant near a south-facing window or outside in a location with plenty of sunlight. Needle cactus requires at least six hours of direct sunlight each day.
  • While needle cactus requires bright sunlight, it’s essential to avoid placing it in direct, intense afternoon sunlight. This can cause the plant to scorch and turn white or yellow.
  • To ensure even growth and prevent one side of the cactus from becoming too elongated, regularly rotate the plant to expose all sides to sunlight.
  • You can opt for artificial LED lights if your area lacks sunlight.

4. Overwatering

Needle cactus is a drought-tolerant plant that prefers to be dry. Overwatering is one of the most common reasons needle cactus turns white.

Here are some tips for the right watering techniques for needle cacti;

  • Allow the soil to dry out completely between watering. Overwatering can lead to root rot and cause the plant to turn white.
  • Use a watering can with a long spout or a squeeze bottle to direct water at the base of the plant.
  • Avoid getting water on the leaves or stems, as this can cause damage or lead to rot.
  • During the winter months, needle cactus enters a period of dormancy and requires less water. Reduce the watering frequency and allow the soil to dry completely between watering.
  • Using well-draining soil can help prevent overwatering by allowing excess water to drain away quickly.
  • Monitor the plant’s appearance and adjust the watering frequency as needed. If the needles appear limp or the plant is turning white, stop watering for some time.

5. Corking

Corking is a natural process in older cactus plants, including needle cacti, where the stem becomes woody and develops a rough, textured appearance.

Corking is a sign of maturity and is not necessarily a cause for concern. If your needle cactus is corking and turning white, it can indicate another problem.

Here are some tips to follow;

  • If your plant appears to be mushy or soft. If the needles turn yellow or brown, addressing the problem promptly is important to prevent further damage.
  • You can prune the damaged stem to prevent further spread if the corking is limited to a specific area.
  • Use a sharp, sterilized knife or pruning shears to remove the damaged area.

6. Diseases & Pests

Cactus plants are susceptible to many diseases and pests, which can be one of the many reasons your needle cactus is turning white.

Some of the most common diseases include;

1. Powdery Mildew

This fungal disease can cause a white, powdery growth on the cactus’s needles. It is often caused by high humidity and poor air circulation.

To deal with powdery mildew, remove any infected parts of the plant and improve air circulation around the plant.

You can also apply a fungicide spray to the plant as directed.

2. Scale Insects

These insects can attach themselves to the cactus’s needles and cause it to turn white. They are often identified by their small, oval-shaped bodies and hard, protective shells.

To deal with scale insects, use a soft-bristled brush to remove them from the plant or apply an insecticidal soap to the plant with care.

3. Mealybugs

These insects can also attach themselves to the needles of the cactus and cause it to turn white. They are identified by their soft, cottony appearance.

You can use a brush to remove them from your cactus plant or any insecticidal spray.

4. Temperature Shock

Temperature shock can cause a Needle cactus to turn white because it can damage the plant’s tissues and lead to losing its green coloration.

This can happen when a cactus is exposed to extreme temperature changes, such as going from hot to cold or vice versa, too quickly.

The best temperature for cactus plants in the USA varies depending on the specific species of cactus.

In general, most cacti prefer warm to hot temperatures during the day, with a range of 70-90°F and cooler temperatures at night, with a range of 50-60°F.

However, some cacti can tolerate temperatures outside of these ranges, and some even prefer cooler temperatures.

Here are some tips to protect your beloved Needle cactus from temperature shock;

  • If you move your cactus from one location to another with a significant temperature difference. Acclimate the plant gradually, exposing the cactus to the new conditions gradually, over several days or weeks, until it has adjusted.
  • Providing shade, such as under a tree or shade cloth, can help protect the needle cactus from extreme temperatures.
  • Stick to a watering schedule that allows the soil to dry out between waterings and avoid watering during extreme temperature changes.

5. Nutrient Deficiencies

Nutrient deficiencies can cause Needle cactus to turn white because they can affect the plant’s ability to produce chlorophyll, the green pigment that gives plants their color.

When a cactus is deficient in certain nutrients, it may lose its green coloration and turn pale or white.

Some important nutrients for cactus plants include nitrogen, phosphorus, and potassium.

Nitrogen deficiency can cause the Needle cactus to turn pale or yellow, while phosphorus and potassium deficiency can cause the Needle cactus to turn dull in color or brown.

If you want to prevent your needle cactus from turning white, here are a few tips to follow;

  • Use a fertilizer that is specifically formulated for cactus plants and contains a balanced ratio of nitrogen, phosphorus, and potassium.
  • Over-fertilizing can be just as harmful as under-fertilizing.
  • Stick to the recommended dosage on the fertilizer packaging, and avoid fertilizing during the winter months when the plant is dormant.

6. Poor Air Circulation

Poor air circulation can cause Needle cactus to turn white because it can lead to the buildup of moisture and the growth of fungal diseases on the plant’s surface.

This can also cause the plant to lose its hardiness and become more susceptible to temperature shock and nutrient deficiencies.

To allow more airflow keep the following tips in mind;

  • When growing multiple cactus plants, ensure they are spaced far apart to allow for good air circulation.
  • A small fan near your cactus plants can help circulate air and prevent moisture buildup. This can be especially important in areas with high humidity.
  • Avoid placing the plant in a closed, stagnant area with poor airflow. Choose an area with good air circulation, such as a spot with plenty of natural light and gentle breezes.
  • Prune regularly; pruning your cactus plant can help promote good air circulation by removing dead or damaged foliage.

7. Accumulation of Salts

If your needle cactus is turning white, the accumulation of salt can be one of the reasons.

This can happen when there is a buildup of salts in the soil from regular fertilization, water with high salt content, or from using water that has passed through a water softener.

The buildup of salt in the soil can cause the plant to lose its ability to absorb water and nutrients properly, leading to discoloration and wilting.

Here are some tips to prevent the accumulation of salts in your needle cactus;

  • If you live in an area with high salt content in the water, use filtered water to prevent salt buildup in the soil. Alternatively, you can collect rainwater for watering your cactus plants.
  • Use a low-salt or salt-free fertilizer specifically formulated for cactus plants, and follow the recommended dosage.
  • Periodically flush the soil with clean water to remove excess salts and prevent salt buildup.
  • Water the plant until water runs out the bottom of the pot, allowing the soil to drain fully.
  • Repotting your cactus plant every few years can help prevent salt buildup in the soil.

8. Frost Damage

The needle cactus is a hardy plant but sensitive to freezing temperatures. Frost damage can cause Needle cactus to turn white. This can happen when the plant is exposed to freezing temperatures, which can damage the plant cells and cause discoloration or wilting.

To protect your plant from frost damage;

  • Move the plant to a warmer location or cover it with a frost cloth or blanket.
  • Provide adequate lighting while protecting the plant from the cold.
  • If your outdoors is very cold, opt for LED or artificial lights.

Austrocylindropuntia Subulata, Pink Eves Pin Needle Cactus, Opuntia Cactus, Opuntia Subulata cylindrica, Austrocylindropuntia subulata

Wrapping Up!

If your needle cactus is turning white, it could be due to various reasons.

Some of the most common causes include sunburn, insect damage, nutrient deficiencies, frost damage, salt buildup, poor air circulation, temperature shock, and disease. By taking the necessary steps to identify and address the underlying cause, you can help your needle cactus recover and maintain its healthy green color.

You may also like: