How to Revive Dying Petunias Properly

Petunias are delicate annual flowers that do not like cold or frosty temperatures. They fade in winter.

Petunias that are dying and wilting typically caused by fungal illnesses like root rot caused by excessive water in the vicinity of roots. Petunias require an extensive irrigation every week. They are not tolerant of excessive watering, which results in petunias’ leaves and flowers to turn brown, resulting in dying petunias.

Yellow leaves are an indication of root rot, lack of enough sunlight or a deficiency of nutrients.

To stop petunias dying, it is essential to find the balance of soil moisture to prevent the onset of root rot and drought stress.

Continue reading to discover the most effective ways to care for your petunias to avoid dying petunias and the best ways to revitalize your petunias to ensure that they can be regenerated and display the flowers…

Petunias Dying From Root Rot (Leaves Turning Yellow and Drooping)

The most frequent reason why petunias die is due to the illnesses root decay and Botrytis that result from over-watering soils, slow draining soils, and pots that do not drain.

Petunias can be indigenous to South America where they thrive in full sun and in moist but well-drained soil with excellent air circulation and low humidity.

The soil surrounding the petunia’s roots is damp, or even boggy, it can create the conditions for fungal diseases like root rot and Botrytis that thrive in moist slow draining soils that remain overly saturated after rainfall or watering.

Even if the petunia is not suffer from root rot, excessive water around the roots blocks oxygen in the soil that is essential for the root’s respiration. If the roots are unable to breathe through the soil because of a lack of oxygen, this hinders the ability of the roots to move nutrients and moisture within the plant. This results in that the plant’s leaves plant to become yellow and then die back.

The plants thrive in soils that are hydrated regularly, about every week. This ensures the proper equilibrium of moisture in the soil, without creating the damp conditions that can cause root decay.

(Read my article on on how you can water your petunias to find out how to determine the best timing for watering your petunias in accordance with the climate and conditions).

Petunias are tolerant of dry conditions, and they can even withstand drought after they’ve established.

petunias dark pink

The routine of watering thoroughly every week and making sure that the soil does not get too boggy mimics the normal watering pattern of the native petunias.

It is crucial to remember that excessive watering your petunias are not the sole reason for excessive moisture around the roots which causes the leaves to turn yellow

  • Containers and pots that do not have drainage holes in their base. Certain decorative pots don’t have drainage holes in their base, or the holes get filled with soil that has been compacted and block water from draining efficiently.
  • Trays that are placed underneath pots, trays or containers. The plants thrive in pots because of their drainage advantages. If you put your pot in a tray to stop the water from spilling, this will collect the excess water that is left after an episode of watering or rain and creates overly sloppy soil that leads to root rot.
  • Petunias are dying inside hanging baskets. Petunias are the most popular flower for hanging baskets because of their capacity to withstand drought-like conditions. But, some hanging baskets are lined with a plastic sheeting impermeable to water or some other material that can aid in retaining moisture however, it could also block water from escaping at the base of the container. This could cause overly sloppy soil that turns the leaves of petunias yellow and have an appearance of drooping.
  • Too often watering. If you are watering your petunias every day, then you are doing it frequently. Reduce the frequency of frequency of watering to once per week, and then increase the watering frequency during heat waves when your soil’s drying out too fast.

If your petunias are in the soil that is boggy for a long period of time and is suffering from an infection caused by fungal bacteria, it may become difficult to rescue.

But your petunia could be experiencing signs of stress when the excessive moisture hinders root respiration, and it is able to be able to recover if you provide more efficient drainage and use more often watering.

How to Revive Petunias With Yellow Leaves

  • If your petunias have turned yellow in your hanging basket look to determine whether there is a plastic membrane (and take it off) that is preventing the water from draining effectively to improve drainage.
  • Make sure that the petunias in your pots are placed in pots that have drainage holes at the base . Remove any soil that has become compacted at the base of the container. It is recommended to repot petunias using a new pots and soil, then apply 1 inch of gravel to the base of your pot to ensure drainage is good and stop any obstructions to drain holes.
  • Set your petunia pot on a stand or little feet to ensure that the pot is raised by about an inch above the ground. If the pot is placed on the ground, then water could be able to drain away from the base of the pot, but it could be trapped beneath the pot, causing the soil to become boggy. The pot’s elevation allows the excess water to drain from the bottom of the pot, and also prevents the soil from becoming over-watered.
  • Find your potted petunias in an area that is open to full sun and with adequate air circulation in order to mimic the conditions in their native habitat.
  • Make sure to plant your petunia in a multi-purpose compost because compost can stay damp (so that your petunia will not die because of the drought) but also is a porous free drainage structure to ensure that roots don’t get sitting in a boggy environment.
  • If your petunias are cultivated in garden boarders, you must alter the area of planting by adding plenty of compost to ensure that the soil is well-drained conditions that allow for the growth of petunias. In the event that your soil has a tendency to be boggy,, then move your petunias into pots.
  • Do not plant petunias in clay soils since clay holds excessive moisture for the petunias to withstand and the clay’s structure soils can be too dense for the roots of petunias to grow properly.
  • Reduce your watering frequency to once a week. Petunias are durable and drought-resistant due because of the fact that they have South American origins. If you water your daily, then you are overwatering your petunias, and that is why they’re becoming yellow.

If you adhere to the most effective methods of caring for your the petunias ( full sun with good drainage, and watering at least once a week) then the soil will be able to dry out , and the plants will recover.

It is crucial to note that petunias that are in soil that is saturated for a long period of time will usually fade and are not able to be rejuvenated.

Petunias Wilting and Dying

The most frequent cause of the death of petunias is due to excessive watering and damp soil, which can cause root decay.

Petunias are susceptible to wilting and then die back because of waterlogging soils, compacted soils that are heavy as well as heat stress especially after the plant has been planted.

Petunias require a balance in soil moisture, which can be achieved by placing them in multi-purpose compost and watering with a good soak every week.

There are certain elements that increase the chance of your petunias dying because of drought stress:

  1. Planting petunias in small , shallow pots. Petunias are able to thrive even when they are crowded into pots, creating an impressive display of flowering in mass. But in pots that are really small, they are less able to hold soil, which means they have less moisture capacity and drying out much faster.
  2. Compacted soils. In heavy, dense compacted soils, the growing root system may struggle to establish itself and gain access to water. Petunias require compost that is aerated and has pores that allow the roots to develop and get to the deeper part of the soil, which allows them to withstand drought. If the roots are unable to develop due to the soil’s heavy, and they remain nearer to the surface of the soil which causes them to dry out faster and causes the petunias to fade.
  3. The application of peat compost is a good idea. Petunias prefer to thrive in full sunlight and require watering every week. The sun’s rays could cause the soil to dry out during periods of watering. If the compost contains an excessive amount of peat, it will be baked hard and turn into hydrophobic, which means it snuffs water from the surface. The water then flows across the surface of the soil, and then down the sides of the hanging basket, pot or garden boarder, without getting into the soil and getting to the roots. Insufficient water causes the petunias fade and then die back.
  4. The intense heat and the excessive air circulation can cause drying out of hanging baskets, in particular. Petunias prefer full sun because they encourage flowering. However, they are prone to wilting because of heat waves and winds that drain moisture from the soil and leaves. Petunias are able to withstand drought and occasionally wilt to decrease the surface of their leaves, and reduce the loss of water before waking to full strength when temperatures cool down.
  5. The shock of transplantation causes the plant to wilt. It may take a while for the root system of petunias to establish after the planting, which leaves them susceptible to drought. Additionally, the abrupt change between the growing conditions when they are grown in a greenhouse prior to purchasing (or maybe grown from seeds your own in a green house) and the environment of your garden may cause the petunias to lose their color briefly as a sign of transplant shock.
  6. If you water your petunias in a way that is not enough, it the plants to wilt. While petunias don’t typically require as frequent watering as others, it is recommended that they must always be properly watered. If you are watering too lightly then only the soil’s surface is saturated. This causes the roots to expand closer to the surface in order to get access to the water, which makes them be more susceptible to drought.

Lack of Fertilizer can Cause Yellowing Petunia Leaves

Petunias aren’t necessarily heavy feeders , and they usually flower more often in soils that have medium to low fertility because too much nitrogen can hinder flowering.

But if your particular variety of petunia is a robust grower and you place them are in pots that are small (smaller pots are less able for soil, and consequently smaller nutrients) or maybe on a garden boarder, and are competing for nutrients with other plants, then they might require fertilizer to green the leaves and encourage growth.

Personally, I would suggest an overall, well-balanced liquid fertilizer like miracle-gro , which has all the nutrients in the correct concentration for the petunias to flourish.

Always follow the manufacturer’s guidelines carefully and be aware that applying more fertilizer than recommended will not produce more results or cause flowering to be less, so use only the amount recommended by your gardener.

If you apply a well-balanced fertilizer the leaves of your yellow petunias will show signs of healing over the next few weeks.

How to Revive Wilting Petunias

  • Plant your petunias in a container which is at least 12 inches in diameter with the same proportional depth if you reside in a climate that is hot. It is possible to be able to plant petunias in smaller pots in colder regions with more rain and more cloudy days. But a bigger pot is better suited for warmer climates since it will hold more soil and retain more moisture, which will stop the petunias from dying.
  • Add a layer of compost prior to planting the petunias. Compost is an aerated, more dense texture and holds in moisture, that allows the roots of petunias to grow much more easily after planting. If your petunias are growing in dense, heavy soils, the best option is to move them into containers and pots, and then replant the compost in. The roots of the petunia are able to get access to moisture and prevent the flowers and leaves from dying and wilting.
  • Do not plant petunias in a compost which contains peat. Select peat-free compost whenever it is possible since peat compost is not just harmful to the environment, but can also divert water away from the surface as it drys out, and stops the water from reaching the roots, causing drought stress. Check the bag of commercial compost to ensure it’s free of peat prior to purchasing or using garden compost to plant your own petunias that have a porous structure which allows water to penetrate into the root system, even when the soil is dry.
  • It is recommended to water more often during hot waves, and attempt to cushion powerful winds to avoid the plant from wilting. Petunias typically require watering every week in order to maintain the proper balance of moisture and to prevent the plant from wilting. In the heat, however, you should increase the frequency of watering to every two or three days to avoid the plant from wilting. Petunias like airflow however, it is important to remember that windy conditions can cause a loss of the leaves of moisture and cause wilting. If you can, move pots of petunias into a more protected area when it’s particularly windy and make sure to water them well to allow them to recover from the wilting.
  • The shock of transplantation after planting can be reduced by using the use of a good potting soil or compost that holds in water so that the roots draw in water more easily when they adjust to changing soil condition. It is recommended to water once every couple of days following planting, with a good soak that encourages the development of healthy roots and ensures that the plant will be more resilient to dry weather and is less likely die when it matures. Find your petunias in the sun, and with regular watering, your petunia will be able to recover from shock after transplantation and regain its look of wilted.
  • Make sure to water your petunias thoroughly instead of a gentle watering. A deep soak to ensure that water drips out from the bottom of pots ensures that the water is reaching the roots and encourages the development of healthy roots that increases the petunia’s resistance to drying and hot conditions, and also prevents the petunia from dying.

A petunia that is dying and wilting leaves will be able to recover from drought in one week, provided that you have created the proper conditions by using a good moisture-retaining compost and watering every week at least to encourage stronger roots for more drought-resistant petunias.

Petunias Dying in Cold Temperatures

The Petunias originate from the warm temperatures in South America and often die back after an sudden frosts or a large change of temperature (hardy for USDA zones 9-11)

Petunias are therefore delicate and are often thought of as an annual plant suitable for pots hanging baskets, hanging baskets and garden boarders in colder climates. Petunias fade as temperatures drop in the Autumn or Winter, and often is dead in spring due to late spring frosts.

If you reside in a climate that is cold and there is a risk of frost, then plant petunias in pots, or hanging baskets to transfer them to an enclosed garage or greenhouse until the risk of frost is gone.

The horticultural fleece may also be able in protecting cold-sensitive petunias from freezing nights and frosts that could be beneficial if they are placed in garden boards and are not able to be moved inside to protect them from freezing.

Petunias Require Full Sun

If your petunia is showing an unruly, leggy growth and only a few flowers and an appearance that is dying, then it needs more sun.

Petunias are adapted to grow in open areas, which is typical of more temperate climates in South America and prefer at minimum 6 hours of sunlight to show the most beautiful flowers.

To make sure your petunias are as healthy as they can be and also to display your flowers it is essential to place your petunias in the most sun-drenched part of your garden.

The longer hours of sunlight can also help reduce the possibility of mold and root rot through creating a more dyed environment that allows your petunias flourish.

Transfer petunias from pots, containers, or hanging baskets to an area with full sun and aid in reviving your petunias. New healthy growth that will include more flowers is expected to appear in the coming weeks.

Petunias Turning White

The reason that petunias become white is due to powdery mildew or mold that is due to excessive humidity, frequent watering in the evening, and not the morning, and lack in air flow.

Make sure to water your petunias early in the morning, because this helps them to absorb water prior to the sun-filled day ahead. It also allows any water to dry out in the sun prior to the cool evening.

If you don’t water your plants enough in the evening, your petunia will need to rest in humid and damp conditions longer, which can lead to mildew that is powdery and has a look of white on leaves.

Petunias are also accustomed to the open spaces that have good air circulation from breezes that are occasionally present. If they’re located in a closed area and especially with high humidity, they’re more susceptible to turning white due to the growth of powdery mildew.

Do not apply any fertilizer when your petunia’s leaves are turning white . mildew that is powdery can affect the lush green growth more than established leaves.

Powdery mildew doesn’t necessarily cause harm to petunias to a large extent , and petunias are usually in a relatively healthy way. Learn more about how to treat mildew that is powdery.

Petunias that are in full sun that have good airflow and watered prior to a hot day, to ensure that the water on the leaves will evaporate and they are able to deal better with mildew that is powdery than plants that aren’t in the right conditions to grow petunias.

Key Takeaways:

  • The reason that petunias die is typically root rot, caused by excessive water around the roots due to excessive watering. Petunias must be planted in compost that drains well and watered every week to prevent dying from root rot. In moist soils, petunias will wilt and become yellow with an appearance of dying.
  • Insufficient sun, overwatering and deficiency of nutrients can all result in petunia leaves turning yellow and then die back. Petunias require at least six hours of sunshine to bloom and stop leaves from turning yellow. Petunias grown in small pots may be yellow due to smaller pots that have smaller amounts of soil, and consequently less nutrients. Apply a fertilizer to stop the leaves from turning yellow. Make sure to water your petunias only once a week, and make sure that they drain well. conditions to keep the leaves from turning yellow due to root rot.
  • Petunias may also die due to drought stress. In warmer climates, petunias frequently will wilt when they are placed in pots that are shallow or hang baskets because they are less able to absorb soil, and consequently retain less moisture, which causes the petunia to die in response to drought stress.
  • To bring back a dying petunia, make sure that the soil is damp but drains well. This can be achieved by watering the petunias well every week, and then planting them in compost that drains well. Find petunias that are in full sun with plenty of airflow to aid in their reviving.


Went from a bad gardener to a half-decent one over 10+ years. Super happy to share my tips and tricks with you :)