Potato plants falling over can be an alarming sight for many gardeners as it can mean unhealthy plants that are too tall or leggy. Pruning potato plants can be a solution, although to prune potato plants is not always the correct answer.

Potato Plants in row

Gardeners naturally wonder and worry about these occurrences as it is unusual for healthy potato plants to just fall over by themselves. Let’s go and find out what the root causes may be for your potato plants falling over.

Why Are My Potato Plants Falling Over?

Several reasons could be behind this phenomenon, such as having potato plants too tall to stand by themselves. Although tall potato plants can sometimes be the cause, some gardeners mention that the collapse of these plants could also be due to leggy potato plants.

This is one of the most frequently asked questions among many gardeners who grow potatoes. The sudden collapse of some of your potato plants can indeed be worrying, but the most important thing we need to remember is to keep calm and investigate what could be causing our potato plants to topple over.

Potato plants can fall over for a number of reasons. In this article, we will be going into the possible reasons why this is occurring. We will also tackle options to resolve these concerns, as well as find possible ways to prevent it from happening again. We’ll start with the most common reason.

– Potato Plants Fall Over When They Are Mature

Potato plants normally take 80 to 160 days to mature depending on the variety. Usually, mature potato plants can grow to a length of 1 ½ to 2 feet before they fall over.

– Yellowing Plant

Another sign that the potato plant is mature and ready to be harvested is the yellowing of the plant. Potato shoots and leaves usually turn yellow first before they fall over. These can be signs that the potato plant is ready to be harvested.

– Flowering

Some potato varieties will even flower or fruit when approaching maturity, although this is not a guarantee that the potato plant is ready for harvest. The potato blossoms are an indication that the plant is mature enough to start producing tubers.

When flowers appear, most gardeners recommend removing them to ensure that the potato plants focus their energy on growing their tubers. Gardeners also encourage removing the fruit that grows above the ground, especially if you have curious children or pets around. The fruit contains solanine, which can be harmful when ingested in large amounts.

– How Long Does It Take a Potato Plant To Mature?

Potato plants have different maturity and harvest dates depending on the variety. Some take a shorter time, while others take longer to mature. It is important that we keep track of the dates we plant a specific variety so that we can estimate and anticipate their harvest periods.

– Potato Plants Fall Over When They Grow Too Tall

Potato plant height is an essential factor to consider when you see them toppling over. Potato plants can grow too tall when they have been given too much fertilizer, especially when it’s rich in nitrogen. Nitrogen can encourage potato plants to develop more than usual, and this is evident in the overgrowth of their tall green shoots above the ground.

While the situation may seem ideal, overfeeding the potato plants with fertilizers can discourage the growth of potatoes underground. The lush foliage above the ground consumes the energy of the potato plants and will lead to an empty harvest unless this situation is quickly remedied.

– What To Do

Piling the soil around the base of the potato plants can help them stay stable. Doing this also helps prevent the potato tubers from getting exposed to the sunlight. When potato tubers are exposed to sunlight, they turn green and become toxic.

Staking the potato plants can also help them be stabilized. Individual and grouped staking can be done for multiple potato plants, with varying heights to support mature and developing plants.

– Extreme Temperatures

Potato tubers develop at ideal temperatures of 60 to 70 degrees Fahrenheit. The best time to plant potatoes is when the soil temperature is around 45 to 50 degrees Fahrenheit, as this reduces the chances of the plants encountering warmer soil temperatures when they approach maturity. When the soil temperature reaches 80 degrees Fahrenheit, potato tubers rarely develop. The warm soil condition also causes the plant to fall over.

Potato plants can tolerate light frost, although temperatures below 32 degrees Fahrenheit can cause the plant to freeze, fall over and perish. To prevent possible frostbite for your potato plants, row covers can be used to protect the whole plant down to the ground.

Potato plants in containers are more likely to experience extreme soil temperatures due to less insulation.

– Incorrect Watering

Improper watering can also cause potato plants to fall over. Whether underwatered or overwatered, potato plants can suffer trauma from irregular watering amounts.

Regulate Potato Plant Growth

– Overwatering

Overwatering creates waterlogged soil conditions which discourages soil aeration. Potato plants with root systems choked from excess water can eventually rot. The underground root systems will slowly perish and cause the potato plants to fall over eventually.

– Underwatering

Underwatering is easier to spot as potato plants will often have curled leaves as an early indication of dehydration. Feel the soil with your fingers to check if the soil needs watering. If the soil is dry a few inches deep, you need to water it.

– What To Do

Water potato plants from below to avoid getting the leaves wet. The most ideal time to water your potato plants is in the morning, which allows any wet leaves to dry off in the sun. This also reduces the chances of the potato plant becoming susceptible to fungal infections.

Potato plants benefit from deep, infrequent watering and do not do well with minimal frequent watering. Gardeners also recommend that potato plants should be watered only when shoots and leaves emerge from the garden soil.

– Diseases

There are various diseases that can cause the potato plant to become unhealthy and fall over. Two of the most common ones are early blight and late blight.

– Early Blight

Early blight causes the potato plants to display brown spots outlined with yellow. Initially, the brown spots appear on the older leaves at the base of the potato plants. Early blight in potato plants is caused by the Alternaria solani fungus.

The Alternaria solani fungus is disseminated by fungus spores carried by the wind, through human contact, from infected plants, and from contaminated water. Early blight can also spread through compost materials that contain infected parts of plants, especially if the compost was not hot enough to kill the Alternaria solani fungus.

Early blight spreads readily in damp conditions, and outbreaks of this disease often follow after extended periods of rain. The Alternaria solani fungus can even survive in the soil during winter, where it hibernates until spring.

– Early Blight — What To Do

Severe early blight results in smaller and fewer potatoes, and can also cause lesions to form on the potatoes as well. Early blight risks can be reduced by ensuring optimum growing conditions. This includes proper use of fertilizers, correct irrigation techniques, and pest management. Fungicide may be applied to the infected plants as well, although organic ones are best.

– Late Blight

Late blight is often characterized by large, dark-brown patches on the stems and leaves of the potato plant. Left untreated, late blight can attack the potato tubers, rendering them inedible.

Late blight is caused by the Phytophthora infestans fungus, which is easily spread through the air especially at cool temperatures of around 60 to 70 F. This fungus can cause devastating loss to potato crops if left alone as it can survive cold winters by hibernating inside afflicted potato tubers.

– Late Blight — What To Do

While there is no current cure for late blight in potato plants, there are several ways to reduce the possibilities of late blight infections. Removal of the infected plants is recommended to prevent the spread of the fungus. Spraying with fungicide can also prevent late blight from infesting potato plants. To lessen possible risks, organic fungicides are ideal.

To lessen the risk of any other diseases and infections like fusarium wilt and verticillium wilt, it is recommended to purchase certified seed potato varieties that have been bred to be resistant to most diseases.

Save Potato From Falling Over

– Pests

Pests can be the cause of potato plants falling over. Some of the most common pests that prey on potato plants are cutworms and the Colorado potato beetles.

– Cutworms

Cutworms cut off potato plants at the stem by chewing on the parts close to the ground. The best way to prevent these pests from eating your potato plants is to use cutworm collars, which can be made from all kinds of materials.

– Colorado Potato Beetles

Colorado potato beetles are identified by their yellow-orange bodies with black stripes along their backs. They are about a quarter of an inch to half an inch in size.

Colorado potato beetles lay up to around 500 eggs on the underside of leaves within a five-week period. Once hatched, these pesky little beetles can wreak havoc on your potato plants by devouring their leaves and causing the whole plant to fall over.

These beetles have slowly developed immunity to many pesticides. The most ideal solution to this infestation is to use straw as mulch material for potato plants while encouraging the pests’ natural predators to guard your plants. Crop rotation can also prevent the Colorado potato beetles from spreading and multiplying.

Potato falling over


What to do when potato plants fall?

When potato plants fall, gently support them by staking or propping them up to prevent damage and promote upright growth.

Will too much sun cause potato plants to fall?

Excessive sun exposure can cause potato plants to wilt or droop, but falling is more likely due to inadequate support or other factors.

Are potato plants prone to falling if buried too deep?

Potato plants are not prone to falling if buried at the right depth. Ensure proper planting depth to promote healthy root development and upright growth.


Potato plants falling over is indeed a cause for concern when we are unsure about the reasons why. From what we have discussed in the article above, we have become more informed and aware of the reasons why our potato plants fall over.

  • Potato plants can fall over due to their maturity, and this could be a sign that the potatoes are ready to be harvested.
  • Potato plants fall over due to excess fertilizer causing them to grow too tall. Staking the potato plants can help stabilize them, especially when they are not yet mature.
  • Potato plants can fall over when they are exposed to extreme temperatures. Ensure that your potato plants are kept away from extreme hot and cold soil temperatures by providing the appropriate insulation.
  • Potato plants fall over from underwatering and overwatering. Deep and infrequent watering can help alleviate improper watering methods.
  • Potato plants may fall over due to diseases such as early blight and late blight. To prevent these fungal infections from spreading, fungicides can be sprayed on the plants.
  • Potato plants falling over can be caused by pests such as cutworms and the Colorado potato beetle. Infestation can be prevented by using cutworm collars and crop rotations.

We can now rest easy knowing that we have understood the phenomenon of potato plants falling over. With a little bit of insightful investigation, solving potato plant problems is as easy as eating those delicious tubers!

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