Calibrachoa (also known as ‘Million bells’) is a flowering plant that is a perennial in mild climates but regarded as an annual in cold climates that experience frost as it is not cold hardy and they die back in Winter.
The most common reason for a dying calibrachoa is because of root rot due to overly damp soil. Calibrachoa prefer a soak and dry pattern of watering, so if the soil is consistently damp because of poor drainage or over watering, then calibrachoa leaves turn brown and droop with a dying appearance.
Calibrachoa that has stopped growing or flowering with its leaves turning yellow is because of a lack of nutrients and the plant requires additional fertilizer.
To prevent calibrachoa from dying it is important to get the balance of watering right to avoid root rot or drought.
Keep reading to learn the best practices of care to prevent calibrachoa dying and how to save your calibrachoa so that it recovers and displays flowers…
Calibrachoa Dying of Root Rot (Calibrachoa Leaves Turning Brown)
The most common reason your Calibrachao is dying is because of excessive moisture around the roots.
Calibrachoa are native to South America and Mexico where they thrive in well draining soil, open areas and full sun.
If the soil around the roots is kept damp or boggy then this promotes the conditions for fungal diseases such as root rot which thrive in overly damp soil that does not drain efficiently.
The symptoms of a calibrachoa suffering from root rot are foliage and flowers turning brown (perhaps yellow) with a drooping appearance.
Calibrachoa thrive on a soak and dry style of watering where they are watered generously once per week and the soil is allowed dry out somewhat (without drying completely) so that the roots are not sat in consistently damp soil.
This style of watering replicates the conditions of calibrachoas native environment.
The soil around your calibrachoa can be too boggy because of:
- The use of trays underneath pots or containers. Calibrachoa grows very well in pots and containers, however if you place a saucer or drip tray under the pot then this prevents excess water from escaping after watering or rainfall and causes the soil to become saturated which is the cause of root rot.
- Pots and containers without drainage holes in the base. Calibrachoa requires good soil drainage or the plant dies. If your pot or container is decorative it may not necessarily have drainage holes in the bottom so the excess water cannot escape and the roots develop root rot so the plant turns brown and dies back.
- Calibrachoa dying in hanging baskets. Calibrachoa is an excellent plant for hanging baskets as it can tolerate soil drying out between bouts of watering. However some hanging baskets are occasionally lined with a plastic sheeting or other material that can retain too much water which causes the soil to be boggy and the calibrachoa wilts, turns brown and dies back due to root rot.
- Calibrachoa dying due to over watering. If you are watering your calibrachoa every day then this is far too frequent for the calibrachoa to thrive and flower. Scale back the watering to once per week (2 or 3 times per week during a heatwave or drought for hanging baskets) to replicate the typical moisture conditions of calibrachoa’s native environment.
If the calibrachoa has severe root rot it is very difficult to save it so prevention is better then cure.
However it may just exhibit signs of stress such as a drooping appearance if it is water stressed and it can recover if you create better drainage conditions and water it less regularly.
To revive a calibrachoa plant it is important to:
- Remove any drip trays or saucers from underneath pots to allow excess water to escape so that the calibrachoa’s roots are not sat in boggy soil.
- If your calibrachoa is planted in a hanging basket then try to remove the plastic membrane in the bottom as this could be retaining too much moisture.
- Shelter the calibrachoa from rainfall and refrain from any watering for at least 1 week.
- Keep the calibrachoa in full sun and do not use fertilizer. Cut back any brown or yellow foliage with a sterile pair of pruners. Wipe the blades with a cloth soaked in alcohol disinfectant after each cut to prevent spreading any fungal spores to otherwise healthy plant tissue.
- Always plant calibrachoa in multipurpose compost as compost is able to retain enough moisture for the calibrachoa to thrive, yet it has a structure that allows excess water to drain away from the roots to prevent the soil becoming saturated.
- If you are planting calibrachoa in garden boarders, always amend the planting area with compost to emulate their preferred soil conditions. Avoid planting calibrachoa in clay soils altogether as clay retains too much moisture which causes root rot and results in a dying calibrachoa. If your garden has clay soil or boggy areas then plant calibrachoa in pots instead as it is far easier to create favourable drainage conditions in pots and containers rather then in garden soil.
If you follow the best practices of care, and achieve the right balance of watering so that the soil has a chance to dry out then this significantly reduces the risk of root rot and the calibrachoa should show signs of recovery after a week if it is water stressed.
However it is important to emphasize calibrachoa that has been in saturated soil for a long time often does not revive.
Calibrachoa Dying Due to Under Watering (Wilting Foliage and Flowers)
The most frequent cause of calibrachoa dying is because of over watering and damp soil. However calibrachoa can turn brown and wilt with shrivelled leaves due to under watering.
Calibrachoa requires a balance of soil moisture which is best achieved by growing the plant in good compost in pots, containers and hanging baskets and watering with a good soak once per week.
However if there is a significant heat wave, wind, arid conditions or if the soil is too sandy (or stony) then the calibrachoa’s water requirements can increase.
Calibrachoa in hanging baskets are more vulnerable to drought thanks to their greater exposure to wind and with less capacity for soil compared with pots and containers.
Keep in mind that if your pot or container has dried out completely then the potting soil can bake hard which causes water to run off the surface rather then soak into the soil.
So ensure that you water soil around your calibrachoa slowly to ensure the moisture infiltrates the surface rather then deflects and runs off down the side of the container away from the roots.
There are a lot of factors that determine watering frequency (such as rainfall, temperature and humidity) but in hotter climates or if there is a heat wave, it is best practice to water calibrachoa once every 3 or 4 days to achieve the optimal balance of moisture.
If you think drought is the reason for your calibrachoa dying then test the soil to a fingers depth and monitor the soils moisture throughout the week and water as soon as the soil feels somewhat dry.
This can help you to establish the how frequently to water the pot or basket specifically for your climate, so that the calibrachoa can recover.
A dying calibrachoa with wilted leaves should recover from drought within a week as long once you determine the optimal watering frequency for your climate.
Calibraocha Leaves are Turning Yellow
If your calibrachoa leaves are turning yellow then this indicates a deficit of nutrients in the soil.
Calibrachoa grows quickly and therefore requires additional nutrients in the form of fertilizer to grow, flower and to prevent the leaves from turning yellow.
This is a common problem for calibrachoa growing in smaller pots, containers and hanging baskets as small pots have less capacity for soil and therefore the roots have less access to nutrients.
How to Revive Calibrachoa with Yellow Leaves
To revive yellowing calibrachoa, it is important to fertilize your calibrachoa pots if the leaves are turning yellow with a half strength all purpose fertilizer.
For calibrachoa in pots I prefer to use an all purpose fertilizer such as miracle-gro as it contains all the nutrients that calibrachoa requires at the right concentration to avoid problems associated with too much fertilizer which can burn the roots of your plants.
For optimal flowering and to prevent leaves from turning yellow, use a liquid fertilizer once every 2-4 weeks to keep your calibrachoa in the best condition.
If a nutrient deficit is the problem then your calibrachoa should grow faster and recover from its yellow appearance in the next 2 weeks.
Calibrachoa Requires Full Sun
If your calibrachoa has poor, spindly growth with few flowers and looks unhealthy then it requires more sun.
Calibrachoa are adapted to growing in open areas in warm climates and locations with at least 6 hours of sun in their native South American environment.
To ensure the calibrachoa is healthy and has their best display of flowers it is important to locate your calibrachoa in the sunniest area of your garden.
More hours of sun also help to reduce the risk of root rot through increased evaporation and ensure the plant is healthy so it is more resistant to disease.
Move pots and containers to an area of full sun and locate hanging baskets in a sunny location to help revive calibrachoa.
Calibrachoa Dying in Cold Weather
Calibrachoa is native to warm areas of South America and it is not resistant to frost, although it can occasionally tolerate a light frost (Hardy in USDA zones 9-11)
Therefore calibrachoa is often regarded as an annual flowering plant for hanging baskets and pots in cool climates that experience frost in Winter as they die back in Winter with the foliage often turning black.
However you can protect calibrachoa in cool climates by growing in pots and moving them to a heated greenhouse for the Winter and return them outdoors once the threat of frost has passed.
Horticultural fleece can also help to protect the cold sensitive calibrachoa from cold nights and occasional frost.
Key Takeaways:
- Dying calibrachoa is usually because of fungal diseases such as root rot caused by excess moisture around the roots. Calibrachoa requires the soil to dry out between bouts of watering, so if the plant is over watered or in boggy soil the leaves turn brown and wilt, resulting in dying calibrachoa plants.
- Yellow calibrachoa leaves are cause by a lack of nutrients. Calibrachoa is a heavy feeder due to it fast growth and requires fertilizer once every 4 weeks to prevent yellow leaves and promote flowering.
- Calibrachoa can suffer from drought which causes the leaves to wilt. Calibrachoa in pots and hanging baskets can be vulnerable to drying out too quickly in hot weather. increase watering to once every 3 or 4 days in hot and dry weather.
- Calibrachoa is native to South America and prefers full sun with well draining soil. Calibrachoa in too much shade often has poor growth and few flowers. Ensure calibrachoa is located in full sun for it to recover and display flowers.