Sunflower Petals Falling off: Why it Happens and What to do?

Sunflowers are arguably the most beautiful flowers you see. Those who have flower gardens always include sunflowers growing due to their aesthetic value. But not every beauty lasts forever and sadly we have to say goodbye to good things. In this scenario, after some time, you witness Sunflower Petals Falling off.

Sunflowers’ yellowness is too precious to be wasted. There is no denying that the beauty of Sunflowers goes down the hill when petals are damaged. But why do petals fall off? Will sunflower petals grow back?

In this article, we are answering these questions along with some important information about petal damage. So, stay till the end to understand why Sunflower petals bid adieu to the plant.

Sunflower Petals Falling off: What are the reasons?

When petals start falling off, growers start to panic. When they observe this, the first thing they search is, “Why do sunflowers lose their petals”. Well, there can be many reasons for this to happen. Let’s have a look at each reason.

It is a natural phenomenon

Mostly, the petals falling off is a natural process. When the bud grows, petals start to stretch. Then, after some time, pollination happens. Due to pollination, seeds start forming in the outer rings, and then this seed formation process move towards the center. As some more time passes, seeds turn soft and light grey.

When the seed production moves towards the center, the seeds present on the outside turns darkens and florets start to drop off.

Most of the petals drop off and only a barren ball of seeds are left. The falling of petals happens after almost 20 days of blooming. Then, sadly the sunflower dies after blooming.

sunflower dies after bloom
Sunflower petals dying

Not enough Nitrogen

Another reason sunflower petals die off is nitrogen deficiency. The deficiency of Nitrogen disrupts the amino acid production process which produces proteins.

Also, the photosynthesis rate decreases when plants lack nitrogen. The chlorophyll content is reduced which leads to low photosynthesis. As a result, less food is produced which eventually is not enough to feed the whole plant. Thus, leaves start turning yellow, and petals of flowers start falling off.

Watering Problem

A grower searches, “why are my sunflower petals falling off” when he doesn’t know what wrong is happening to the plant. Let us tell you that one thing he might be doing wrong is he doesn’t know how much water he should give to sunflowers.

Both overwatering and underwatering can cause damage to petals. When the plant is dehydrated, it is natural that leaves and flowers are affected. Sunflowers require a lot of water than other flowering plants. Hence, it becomes difficult for growers to water properly and they either end up overwatering the plant or underwatering it.

So, how much water should you add while growing Sunflowers? If the plant is dehydrated, then a general estimate is to add 1.5 liters of water each day for better growth. At least add that much water that will moist the top layer of soil. An average sunflower plant requires 8-liter water per week, so increase the water quantity a little by little with each passing day towards the end of the week.

If the plant is not dehydrated, then water only an inch of the plant. This should moist the six inches of the soil. Moreover, if there is no dehydration, then watering every day is not necessary as well.

Overwatered Sunflower is also not desirable either. Overwatering leads to root suffocation and also the emergence of different diseases like root rot. This condition affects flowering as well and we see petals falling off.

Sunflower Petals Falling off
Petals falling off

Weak roots

When the root structure is weak, water and nutrient uptake is compromised. Due to this, plants are weaker and don’t achieve their full potential. Even if such a plant produces flowers, its petals start falling off quickly.

The weak root structure is surely a reason for sunflower petals falling off. But why does this happen?

It generally happens if the soil is compact or you are not using a good pot. If the soil is too compact, then roots find it hard to grow and “breath”. Thus, the root structure is weaker in this kind of soil.

Moreover, if the pot does not have a hole in the end or is made up of poor material that leaches chemicals after some time, then root structure will be poor too. Poor root structure means water and nutrient uptake will not be optimal and the whole plant including petals will suffer.


When people ask why do sunflower petals fall off, then we recommend looking for pests. Why? Because Pests like Sunflower borers, beetles, cutworms, grasshoppers, moths, etc can also cause petals to drop off.

Sunflower moth lays their eggs on the head of the flowers. From these eggs, larvae are hatched which feed on the sunflower seeds. Due to the feeding, webbing also forms on the flowers.

Sunflower Petals Falling off
Moth on Sunflower

Other insects feed on leaves and stems. This feeding leads to a low photosynthesis rate as the quality of leaves and stems are compromised. And if the photosynthesis rate decreases, then like mentioned above, food production will decrease too, and plants will be undernourished. This is one of many reasons why petals fall off from the flowers.

Several diseases also attack and damage the Sunflower. One severe disease is called White Mold. In this, the phenomenon of sunflower petals turning white occurs. As a result, the flower loses its aesthetic value, and seed production is affected as well.

What to do when petals start falling off?

If it is not natural, then you must have to do something to stop the petals from falling. If you don’t, then all of your efforts to grow this plant will go in vain.

Following are the steps you can take to stop the petal damage:

1) Check whether there is any issue regarding Watering. If you observe that your plant is dehydrated, then immediately give water application. If the problem is water scarcity, then the application of water will stop the petal from falling off. If the problem is overwatering, then all you can do is let the soil dry and don’t water at all for the time being.

2) Look for pests on and around your sunflower plants. Pests are one of the biggest reasons for flower damage around the world. Just like others, Sunflower is also not safe from insect attacks. Pests like Sunflower borers, beetles, cutworms, grasshoppers, moths, etc cause petals to drop off. If you observe any of these insects, immediately start any treatment. It is better if you stick to organic treatments like the application of neem oil.

3) Check whether the plants are getting sunlight or not.

4) Do a soil test if you have the resources. Generally, flowers drop of petals if there is nutrient deficiency. So, if a soil test shows a deficiency in any nutrient, then immediately add it.

What to do when sunflower petals fall off completely?

Imagine you do all your efforts to save the petals from falling off and still you couldn’t manage to succeed? What then? What to do when dwarf sunflower petals fall off does not end and you get only a round ball.

When the petals drop off completely, it is time to cut the flower. During this phase, the back of the head also turns yellow. According to the experts, this back of sunflowers turning yellow is a clear indication that the time is perfect to cut the head. Cut the flower from 12 inches to the head and extract the seeds.

Will sunflower petals grow back?

People in the hope to revive the flowers search on the internet, Will sunflower petals grow back? Well, the answer depends upon the type of sunflower plant you are growing.

If the sunflower is perennial, then in the next season, petals will grow back.

If the sunflower variety is annual, then petals won’t grow back. Annual varieties are generally grown to extract the seeds and to harvest flowers.

Want to know a technique in which you can enhance the blooming phase? Then you don’t want to miss the next section about deadheading!

How to deadhead sunflowers?

Did you know that you can prolong the flowering season of Sunflower by a simple cutting? Yes, it is true and this technique is called Deadhead. In this technique, you cut the stalk of spent bloom to prompt the plant to grow more shoots that will produce more flowers.

This deadhead technique improves your garden as the flowers stay longer. Also, as the deadheading is done on fading/spent flowers’ stalks, the plant then starts looking more tidier.

Note: Deadhead is done before the formation of seeds. Only then, the new floral bloom is promoted.

You can deadhead the plants with scissors, knives, or hand pruners. Before using any of the tools, make sure you disinfect them. This is necessary for safe cutting as chances of any disease or pathogen spread get minimized.

Sunflower Petals Falling off Tattoo

Petals falling off from Sunflowers look aesthetic, doesn’t it? Believe it or not, People have started tattooing them in admiration. Sunflower with petals falling off tattoo is in demand and people spend hundreds of bucks to ink them on their skin.

Not only this, Sunflower petals falling off drawing has been praised by people online. After tattooing, people share images of the design on social media. Generally, those who love nature ink sunflower petals falling off Tattoo.

Have you ever wondered what flowers go with sunflowers tattoo? Well typically, people ink roses and lilies along with sunflowers. You can also request any flower of your liking as well.

Final Words

All-inclusive, Sunflower Petals Falling off may be natural or there may be some other reasons behind this. The reasons that may lead to petal damage are underwatering, overwatering, pests, nitrogen deficiency, and weak roots.

If the sunflower plant is annual, then there is no chance that petals will grow back after falling off. If the plant is perennial, then petals will appear again in the next season. To your surprise, as sunflower petals have outstanding aesthetic value, people make tattoos of them as well. But for a grower, petals falling off is not a pretty sight. That is why do what we have described in this article to prevent it from happening completely.


What do you do when a sunflower loses its petals?

When the petals drop off, it is time to cut the flower. Cut the flower from 12 inches to the head. It happens when the seeds are ripe and the plant has almost completed its age.

Will petals on Sunflower grow back?

If the sunflower is of perennial variety, then petals will grow back in the next season. But if the sunflower is of annual variety, then petals won’t grow back and it is time for the flower to die permanently.

How often should you water a sunflower?

If the plant is dehydrated, then a general estimate is to add 1.5 liters of water each day for better growth. At least add that much water that will moist the soil top layer.

An average sunflower plant requires 8-liter water per week, so increase the water quantity a little by little with each passing day towards the end of the week.

If the plant is not dehydrated, then water only an inch of the plant. This should moist the six inches of the soil.

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I am a graduate in Agriculture Sciences and have been doing gardening for over 7 years. I am also a professional and certified Article & Blog Writer. I am happy to share my years of experience in gardening with all of you through my writings. In addition to this, I do extensive research on every topic to enrich readers with valuable knowledge.