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Why Are My Sunflowers Wilting? (7 Common Causes)

Why Are My Sunflowers Wilting? (7 Common Causes)

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A wilting sunflower is a sad sight, indeed. We are all used to the magic of these sun-loving giants’ open faces brightening up even our darkest days. But how can you keep them from drooping, and why do they sometimes start to wilt?

Sunflowers often wilt due to various reasons ranging from a lack of sunlight to pests and insufficient nutrition. A number of tried-and-tested solutions exist to revive wilted sunflowers. However, one should always take the necessary precautions in trying to keep them from wilting.

Although these yellow beauties are hardy and easy to grow, they sometimes need extra attention and tender loving care.

Why Do Sunflowers Wilt?

Sunflowers wilt when they are too dry, too wet, unhappy, or ill, to name only a few reasons. These plants typically bloom in summer and a portion of fall.

Suppose you find your sunflowers wilting and unhappy in the blooming season. In that case, it can be due to numerous factors varying from their environment to being attacked by pests and diseases.

There are over 60 different types of sunflowers; some varieties are only seasonal while others are perennial; some are grown indoors and others outdoors. Some are dwarf-like, while others can grow up to 15 feet tall with flowerheads 1 foot wide.

Whatever shape or size you’re growing at your home, they all have one thing in common: if they aren’t happy, they will start to wilt.

What Can Cause Sunflower Wilting?

Sometimes, though, when the blooming season arrives, you might feel that your adult sunflowers or young sunflower plants are wilting for no apparent reason. Well, turns out there is a myriad of reasons:

Cause of wiltingDetail
Too much waterSunflowers can survive on very little water, so overwatering them will lead to ‘wet feet,’ leading to rotten roots and wilting. These flowers also don’t like water on their flowerheads and leaves as it might lead to drooping or wilting.
Too little waterSunflowers are quite hardy and won’t easily wilt from a lack of water. However, if they are left without any water for a prolonged period, they might wilt and eventually die.
Nutrient imbalance in the soilThe essential nutrients your sunflowers need are carbon, hydrogen, oxygen, nitrogen, potassium, and phosphorus. Without these nutrients, your adult sunflower plants will start to wilt, and your young plants will be unable to develop correctly. Young plants are incredibly fragile when it comes to soil quality and growing conditions. They might not grow leaves, or they will have no roots or flower development.
Too much sunlightThey’re not called sunflowers for no reason: they need and love the sun. Plants get their energy from sunlight. However, chlorophyll and carotenoid (the two photon-capturing molecules) will absorb more energy than needed if the plants get too much sunlight. This over-absorption leads to the generation of certain reactive species of oxygen, which will destroy your sunflowers.
Too much heatAlthough sunflowers thrive in full sun, scorching temperatures might cause your sunflowers to start wilting. According to the Daily Press, plants undergo a process called transpiration. Essentially, it means ‘sweating’ from the pores of their leaves. Sweltering temperatures can cause the plants to exceed their transpiration rates, at which point they will start to droop and wilt.
Pests and diseasesFusarium, Phytophthora, and Pythium are all fungi or plant parasites that lead to various plant diseases. Young plants are often attacked by caterpillars and spider mites, which cause wilting and yellowing. Another disorder that occurs quite commonly in young plants is damping-off, which is caused by a fungus or mold. Damping-off causes young plants’ leaves to wilt and turn a green-gray or brown color. Adult sunflowers are in danger of all sorts of pests like wireworms, cutworms, and beetles. These pests need to be destroyed; otherwise, your sunflowers will start wilting and never grow and bloom to their full potential.
Shock from transplantingAll plants, young and old, suffer immensely when they are transplanted. They end up in a new place and are physically abused: it’s called transplant shock. With transplanting, you also disturb the well-established roots of the sunflowers. All of the above factors will most definitely cause them to wilt and droop.

Whether you’re a seasoned gardener or you’ve developed a sudden onset of the green-finger syndrome, you probably want your sunflowers to happily reach for the sun and light up your life. So, how can you prevent them from wilting altogether?

How To Avoid Sunflower Wilting?

In 2014, a German by the name of Hans-Peter Schiffer had a sunflower that grew itself into the record books by reaching an astonishing height of 30 feet.

Although you might never produce such giants, you can take some precautions and follow some guidelines in trying to keep your sunflowers from wilting:

Give Them the Right Amount of Water

Sunflowers don’t like wet feet, so you should always ensure that you don’t give them too much water. The amount of water you give them greatly depends on where they are in their growing process.

Seedlings need to be watered around the roots, while adult plants only need water once a week when the soil around them has clearly dried out. Then, you should water deeply so that the roots are properly moistened.

Although sunflowers hardly ever wilt from too little water, it is a possibility. If you stay in an area that rarely sees any rain, you need to make alternative plans for when you go on holiday or leave home for a prolonged period.

Ask a friend or family member to water your sunflowers once a week. Another great idea is to install a drip irrigation system that works on a timer.

Ensure the Soil has a Healthy Nutrient Balance

Sunflowers get essential nutrients from the soil they grow in. Too much of one type of nutrient might cause them to wilt or even die.

Too much manganese, for instance, will lead to yellow leaves and wilting. On the other hand, too much boron can downright kill them.

If you suspect that your sunflowers are wilting due to poor soil quality, you can do some research on the best fertilizer for your garden and area. A slow-releasing fertilizer is often a good choice for sunflowers.

Avoid Too Much Sunlight and Heat

Sunflowers love the sun and are pretty hardy. However, more than 8 hours of sunlight and extremely hot conditions can cause them to start wilting.

The ideal temperatures in growing sunflowers are 70-80 degrees Fahrenheit. If the temperatures get too hot, try covering your sunflowers with a shading net or cheesecloth.

Control Pests and Diseases

Although they aren’t usually prone to pests and diseases, you might find yourself waking up one morning staring at wilted sunflowers infested with pests or diseases. Bugs, caterpillars, worms, and spider mites can be detrimental to sunflowers.

Always ensure that your beds are weed and debris-free. You can also try spraying your plants with the following home remedies:

  • Bugs: One part ammonia mixed with seven parts water;
  • Mites: One tablespoon dishwashing soap mixed with one gallon (4.55 liters) water;
  • Fungal diseases: One teaspoon baking soda mixed with one quart (0.94 liters) of warm water.

These are just a few precautions you can take in trying to ensure that your sunflowers never wilt, but it’s not always that easy. If your sunflowers do wilt and droop from a lack of the necessary precautions, it is sometimes possible to revive your wilting sunflowers.

How to Revive Wilting Sunflowers

Sunflowers are not only beautiful to look at, but they also attract pollinators. You can do your part for the ecosystem by reviving your wilted sunflowers so that bees, birds, and butterflies can start feasting on them once again.

How to Revive Sunflowers Growing in Beds

More often than not, a grown wilting and drooping sunflower signifies that it’s reached the end of its blooming cycle. If the plant is still young or midsize, though, you can try to revive it by doing the following:

  • Give it more water. Sunflowers often wilt and droop from a lack of sufficient moisture.

You can do the following test to ascertain whether your flowers need water: Stick your finger into the soil around the flowers – if the first inch of the earth is dry, your plants need deep watering.

When watering your sunflowers, always make sure that the leaves and flower heads don’t get wet.

  • Support the stalks. Top-heavy sunflowers will start to droop, and drooping often goes hand in hand with wilting.

You can easily give them more support with a bamboo stake or some type of trellis. A great tip is to use ties that are covered in fabric. They will be much gentler on the stems.

How to Revive Sunflowers Growing in Pots

Potted sunflowers are most susceptible to drooping and wilting. Wilting is often due to restricted root development due to hardened soil or wrong pot size, poor drainage, or dehydration.

Smaller varieties are perfect for planters, but you need to ensure that your bigger varieties are planted in pots where they will thrive in.

A good measure is to use a 10-12-inch (25-30 cm) pot for varieties that grow up to 2 feet (1/2 meter) and a 3-5-gallon (11-19 liter) pot for varieties growing up to 4 feet (1m) or taller.

Hardened soil will not let water through to the roots of the sunflowers. To save your sunflowers, you can try to replant them into a larger pot with superior quality potting soil.

Your potted sunflowers might simply be dehydrated and in desperate need of weekly watering. If it doesn’t rain, be sure to water them once a week.

If you stay in an area that gets regular rainfall, keep in mind that sunflowers can also wilt from too much water. Luckily, because pots are movable, you can save them from drowning by moving the pots to an alternative, more ideal position.

How to Revive Cut Sunflowers

The very reason you might’ve initially planted sunflowers might be because you want to put them in vases around your house so that you can marvel at their beauty all day long.

But there will be no marveling if they prematurely start to wilt and droop. Here’s what to do:

  • Water them properly the day before so that they are well hydrated and fresh on the day of cutting;
  • On the day of cutting, cut them while the dew is still there – around 10 a.m.
  • Prepare a bucket of warm water and place them in the bucket immediately after cutting;
  • Arrange your vase but make sure that you remove all leaves from the bottom half of the stems to avoid rotting.

Now that you have arranged your stunning masterpiece, you can follow these guidelines in ensuring that your cut sunflowers don’t start wilting or drooping:

  • Give them fresh water daily or as soon as the water starts to discolor. With this water change, you can also gently wash the stems and perhaps cut them an inch or so shorter.
  • Nourish the stems by adding sugar, bleach, or flower food. The latter is available at most nurseries and flower shops, but you can also easily create your own.

Mix 1 tablespoon of sugar mixed with 2 tablespoons of lemon juice and 1 quart (4 cups) water. Another alternative for delaying bacteria growth is to add ½ teaspoon of bleach.

Martha Stewart’s website on floral arrangements even suggests mixing any 12-ounce can of clear lemon-lime soft drink with one gallon of water.

  • Regularly cutaway decaying stems as they can quickly spread bacteria to the other healthy stems.
  • Place your vase in a cool location. Keep it from direct sunlight and hot and drafty rooms.

Final Thoughts

Be sure to treat your sunflowers with much love and attention to keep them from wilting. Make sure that they aren’t overwatered, suffer from pests and diseases, or grow in poor conditions.

It doesn’t matter what variety you decide on or whether you plant them in beds or pots. If you treat them right, they will make your days cheerful and bright.