Geranium leaves turning red may look pretty, but you should immediately find out why this is happening, as your plant may be stressed. There are so many reasons why geranium leaves can turn red, so you need to carefully examine your plant to make sure that it is not in danger.
Continue reading to discover the signs and symptoms of sick geraniums and how you can help them thrive again.
Why Are My Geranium Leaves Turning Red?
Your geranium leaves are turning red because of fluctuating temperatures in their environment, overwatering or underwatering the plants, or not giving them enough nutrients. This problem can also arise due to transplant shock, fungal disease, or an unsuitable soil pH.
Your geranium plants may look prettier when their leaves turn red, but red leaves can be a cause for concern as they indicate a stressed plant. There are so many reasons why geranium leaves can turn red, and here are the most common ones:
– Fluctuating Temperatures
The most common problem your geranium plants face that will give them red leaves is low temperatures. Geranium leaves mostly turn red in early spring or fall. As a heat-loving plant, geraniums can become shocked when the temperature starts to fluctuate or when it gets cold at night.
Geraniums do not like cool temperatures as they are better suited for USDA hardiness zones 10-11. You should take your plants indoors when it is getting cold and wait until the soil temperature warms up in spring before you plant your geranium outside again.
– Watering Problems
Geranium leaves can also become red when you do not water the plant as you should. If you overwater your geranium, the leaves can become red. The same symptom can also occur if you underwater the plant, but most of the leaves will also become brown and wither away.
You should water your geranium as soon as the soil or potting mix becomes dry. Do not give them too much water or too little.
– Nutrient Deficiency
The deficiency of nutrients in geraniums can lead to some leaves turning red, but it depends on what nutrients are lacking. When your plants are lacking in magnesium, nitrogen or phosphorus, they can lose their green coloration and their leaves will become red, yellow or brown.
If your geranium leaves are becoming red because of nutrient deficiency, you should administer an inorganic water-soluble fertilizer to the leaves of the plant. Spray foliar fertilizer on your geranium leaves every two days for two weeks until the leaves become green and fresh again.
– Acidic pH
Unsuitable soil pH is another factor to consider when your geranium turns red. Geraniums prefer a soil pH of around 6.5. Some gardeners mistakenly make the soil acidic instead of just slightly acidic. If the pH of your soil falls lower than 5.8, the leaves of your geranium will become red, signifying stress.
You should test the soil you are using for pH. If the pH is lower or higher than what is needed by the plant, use either baking soda, vinegar or a pH booster product to correct the pH.
– Transplant Shock
Not transplanting your geranium carefully can also make their leaves turn red. When transplanting your geranium to overwinter or in early spring, do not damage the roots. Also, make sure that the temperature is relatively stable as fluctuating temperatures can cause red leaves.
You should also wait a day or two after transplanting before watering your geranium. Make sure that you do not water your plants with cold water.
– Fungal Disease
A fungi species called Puccinia pelargonii-zonalis can give the leaves of your geranium some red or brown lesions and rings. The underside of the leaves will also become powdery red. While the entire leaf does not become red, it can look fully red from a distance.
You can cure your geranium plants with fungicides if they develop fungi.
– Other Causes of Plant Stress
Always remember that geraniums can become red when they are stressed. This means that if you see red leaves, you should diagnose the plant and make sure that you are caring for it properly.
Preventing Red Geranium Leaves
Here are some useful geranium care tips so your plant does not develop red leaves.
– Correct Light and Humidity
For maximum bloom, you should place the geranium plants where they can get 4-6 hours of direct sunlight every day. Geranium plants love a lot of sunlight, and they can become yellow or pale when there is not enough light.
Geraniums also love humidity, so you should water your plants by misting them regularly. For indoor plants, you can install a humidifier so that you do not have to mist the plants often.
– Right Temperature Ranges
Geranium is a heat-loving plant suitable for USDA hardiness zones 10-11. If you grow the plant in cooler regions, it can become an annual. You should bring your geranium plants indoors during late summer or early fall when the temperature drops to lower than 55 degrees Fahrenheit at night.
You should wait until the soil becomes 60 degrees Fahrenheit or warmer before you plant your geraniums outside.
– Watering Correctly
Remember that watering problems can stress your geranium plants. You should occasionally dip a finger or moisture reader into the soil to check. If the soil is dry, water your geranium thoroughly. You should water your plants every 3-5 days according to the temperature and location it is in.
Water your geranium leaves by misting them every day or two to keep the leaves and flowers looking fresh.
– Necessary Nutrients
Geranium plants are not heavy feeders, so you should only feed them with half-strength fertilizer. You can use any flower fertilizer with an NPK ratio of 5-15-15 or 4-10-10. Fertilize your geraniums weekly with flower fertilizer before it blooms during the late spring or summer months.
To maintain the multicolor, pink, purple, red, or white flowers of your geranium, make sure that it is not lacking in nutrients.
– Pruning Your Geranium
You should pinch the stems of your geranium to promote bushiness. To encourage a longer bloom time, remove spent flowers. Prune your geranium foliage every month to encourage new growth.
If the red leaves are dying, you should remove them immediately. You can, however, leave the red leaves in autumn for a beautiful look as many plants have red leaves during that time. If you will overwinter your geranium, remove the red leaves before you bring them indoors.
– Repotting
If your geranium looks frail, it is time to repot it. You should repot the plants in spring when their potting mix or soil is no longer suitable to hold them.
The geranium potting mix should be well-draining, properly aerated, and able to hold moisture. If the media cannot hold moisture or does not permit water drainage, you should repot the plant into a new pot and potting mix.
Remember that when repotting your geranium, you should be careful with the roots as transplanting geranium usually stresses the plant and causes other geranium leaf problems.
– Prevent Pests
Pests such as mealybugs, aphids, whiteflies, spider mites, snails, etc. can disturb your geraniums even if they are indoor plants. You should repel these geranium pests with pesticides. If you see an unwanted bug near your geranium, you should pick and kill it immediately.