Why Are My Crown of Thorns Plant Leaves Turning Yellow?

Euphorbia milii, the crown of thorns plant, is a popular decorative succulent. Crown of thorns grows as a landscape plant or potted for use indoors and out. Euphorbia milii displays:

  • Graceful, thorny stalks
  • Bright green leaves
  • Vibrant flowers that bloom even in winter
Leaves of Crown of Thorns turning yellow
Crown of Thorns bloom with yellow leaves in background | PlantCareToday

The crown of thorns plant needs proper care if it’s going to look its best year-round. With the right environment, you can prevent your crown of thorns plant leaves turning yellow.

Details on Crown of Thorns Plant Care

Yellowing Crown of Thorns – Is That Normal?

Given proper care, a crown of thorns plant has emerald green leaves and flowers in white, pink, red, and even yellow. Though usually considered a small succulent, a healthy crown of thorns typically grows up to two to three feet tall.

Like most succulents, the crown of thorns plant can begin to lose its bold colors without proper care. If anything in their environment is off, leaves start to turn yellow and drop off at a faster rate than usual.

Yellowing can be due to many different environmental factors. Often, succulent plant leaves shrivel and yellow due to lack of water. But, other stress factors can also cause yellow leaves, from rapid temperature changes to poor soil quality.

What Do Yellowing Crown of Thorns Leaves Indicate?

There are a couple of different reasons that your crown of thorns might be starting to yellow. Many gardeners immediately assume it’s due to underwatering.

Underwatering is usually accompanied by telltale shriveling and wilting.

With succulents like the crown of thorns, overwatering tends to be more of an issue for plant health. As a desert plant, the crown of thorns doesn’t need very much water to survive. Too much, and it can cause damage to the leaves on a cellular level.

You should stick to watering your crown of thorns roughly once per week. Allow the soil to dry between waterings. You can water more or less as needed, depending on factors such as the size and location of your plant.

Sunlight is another important consideration with the crown of thorns. Like most succulents, they do best in full-sun that mimics their natural environment.

Crown of thorns plants also prefer higher temperatures. Move them if possible or shelter them when frost begins to hit. Otherwise, leaves may start to yellow, and the plant can eventually die.

In some cases, you may see your crown of thorns plant leaves turning yellow simply because they’re not getting the nutrients that they need. A high-phosphorus environment can help mature plants to thrive in your garden.

How To Control Crown of Thorns Plant Leaves Turning Yellow

A proper care schedule can prevent the leaves of your crown of thorns from turning yellow. It’s important to water and fertilize regularly. If you live in a four-season area, you will want to move your plant depending on the time of year.

Question: Is Crown of Thorns Poisonous?

There are a couple of things that you can do to keep your crown of thorns from turning yellow:

  • A regular watering schedule is vital to good plant health. For most gardeners, watering weekly will suffice. But, remember to restrict watering when it begins to get cold.
  • Avoid adding fertilizer during winter months and prepare your plant for next years’ bloom.
  • Using the right kind of potting soil helps to ensure that your crown of thorns never ends up overwatered. Provide plenty of drainage for the roots system. The plant will only take the water  it needs to survive.
  • Adding pumice to your soil is a good way to provide drainage for succulents such as the crown of thorns.
  • You can also add components such as sand or perlite to your soil to help break it up.
  • Some gardeners like to add peat moss for both texture and nutrition.
  • If your plant is not getting the nutrients it needs from the soil, add liquid fertilizer. It’s best to fertilize when first planting using a slow-release fertilizer. Afterward, apply half-strength fertilizer as needed until your plant is back to its bright, vibrant self.

If you give your crown of thorns plant proper care, it can thrive for years. Prevent yellowing by giving your plant the right level of moisture, sunlight, and nutrients.

This allows this desert succulent to thrive.

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