Marigold Leaves Turning Purple (3 Reasons And Solutions)

You’re working hard to have a good production of marigolds. But you see some defects. Your marigold leaves are turning purple! This should be heartbreaking to you! But what are the causes behind it? Well, we’re going to know about it here! 

So, wonder- why are my marigold leaves turning purple?

Phosphorus deficiency is the first concern for marigold leaves turning purple. Besides, powdery mildew on marigolds is also a significant cause of this issue. Not only that but fungal infections also play a vital role. Fungal infections like white mold infection also result in marigold leaves turning purple. 

We’ve got the details of its causes and solutions. So, you can go through it if you’re able to bear it sometimes.

Sounds good? Let’s just get started then!

3 Reasons with Solutions for Marigold Leaves Turning Purple

marigold leaves turning purple

Well, marigold leaves purpling can be due to a lot of causes. But you’re confused about everything. Because you don’t know what are the reasons behind it. Well, we’re here to help you out! We’ve got the list of causes with solutions for this issue.

Reason 1: Deficiency in Phosphorus

Purpling of leaves can be caused by several factors. But the most prevalent is a phosphorus shortage. Phosphorus is a critical ingredient for plant growth, focusing on roots, blooming, and fruiting. 

Marigold plants stop growing at times. It happens due to phosphorus deficiency. 

The older leaves begin to develop a drab, dark green that eventually turns purple. The purpling starts at the leaf’s tips or undersides and spreads over the entire leaf.

But the addition of phosphorus won’t help. Moreover, artificial fertilizers with high phosphorus are extremely polluting.


Begin with a soil analysis. A soil test will disclose the amount of phosphorus that is accessible. It would also identify any other factors that may influence phosphorus absorption. 

For now phosphorus levels, use bone meal, rock phosphate, and superphosphate. Phosphorus level below 30 ppm indicates its deficiency. You can also use manure, or compost to raise them gradually. The measurement to use would be mentioned with the products

You can get your rock phosphate from our suggestions below-

You can also consider the weather. Plant roots can’t absorb phosphorus properly in cold, moist soil. 

In the early spring, signs of phosphorus insufficiency are common. The plants would recover as the weather warms up if the reason is cold. So, warm places for the plants are strongly recommended to resolve this issue. Sites getting proper sunlight are good for it. 

Reason 2: Powdery Mildew on Marigold

Powdery mildew is a fungus that causes white mold to form on marigold flowers. The marigold leaves gradually become purple as a result of this.

Moreover, some leaves also grow abnormally after being infected by this type of fungal disease. They might grow small. 

Spores can spread through the air and infect other plants in your garden. Overwatering and overfertilizing with nitrogen can also increase fungal growth.


Plants should be spaced far apart to allow for adequate airflow. Additional therapy may be required in extreme situations. Apply a fungicide to your plants in the spring before powdery mildew appears. Then, as needed, continue throughout the year.

Keep an eye on your plants. Don’t forget to take care of any unhealthy leaves.

You might be perplexed about which fungicide to apply. So, we’ve come up with some ideas for you!

These are the products you can easily have faith in for their outstanding qualities.

Mix a teaspoon of baking soda in a quart of water for a quick fix. Then spray the plants extensively. So that the solution can only destroy the fungus that it comes into touch with. 

Reason 3: White Mold Infection

White mold is caused by the fungus Sclerotinia. As the name says, it causes fluffy white mold on damaged leaves and stems. Other symptoms include wilting leaves and dry, brittle, tan-colored stems in the infection area.

Sclerotia, which are tiny, hard, black formations, can form on infected stems. This eventually turns the marigold leaves purple as an aftereffect.

Mold spores can live in the sclerotia for up to five years. As a result, eradicating this disease from your garden is a difficult task. Under cool, moist conditions, the spores grow into mushrooms, which release more spores.


This infection is incurable and untreatable. So, any sick marigold plants should be removed from the garden. You can either burn or bury the sick plants far away from where you wish to plant them. 

Give new plants plenty of room. Do this when you’re replanting to allow ventilation and keep foliage dry. Reduce the amount of water and moisture you use as much as feasible. Reduce the amount as per as needed for your plants. Keep the humidity from 30% to 50%.

You can use a humidifier to control the humidity. Here are our recommended ones-

These are the main reasons for your marigold leaves purpling. Following our steps to the solution would indubitably help you resolve the issue.

Frequently Asked Questions

Question: What if I overwater marigolds?

Answer: You may need to water marigolds regularly if the weather is too hot. But not otherwise. Too much water can cause waterlogging in the soil. It can increase root rot and the spread of fungal infections. Avoid watering the blossoms since they will become soggy, squishy, and mushy. if you do.

Question: How can I get more flowers on marigold?

Answer: Marigolds do not need to be deadheaded. However, removing fading blossoms regularly encourages the plant to continue flowering prolifically. While watering marigolds, let the soil dry somewhat between waterings. After that, water them well again and repeat the process. In high temperatures, water evaporates more quickly. Marigolds should not be watered from above.

Question: How to choose the best fertilizer for marigolds?

Answer: Use a full-spectrum fertilizer with a nitrogen content of 100 to 150 ppm. Make sure the nitrogen and potassium levels are balanced. For marigolds, it is the best nutrient source. When the soil temperature drops below 65 degrees Fahrenheit, avoid using ammonium fertilizers.

Final Words

So, now we know why are marigold leaves turning purple? But this isn’t a major concern. Make sure to follow our instructions to resolve the issues simply.

Let’s give you a tip now. Marigolds should not be fertilized while they are growing. A diet high in nitrogen encourages luxuriant foliage at the price of blossoms.

Happy gardening!

Leave a Comment

Your email address will not be published. Required fields are marked *