A garden staple is a lovely rose bush. They are timeless and classic. A variety of rose bushes adds an abundance of colorful flowers to your yard. Roses only require minimal maintenance and grow a few feet tall. You can grow them almost anywhere. However, some gardeners find yellow leaves on roses and worry that they killed their gorgeous bushes.
Luckily, rose bushes are hardy and can survive in most weather. They handle warm, Mediterranean climates as well as cold, frosty winters. The appearance of yellow leaves destroys the beauty of the bush and indicates something is wrong with its health. Roses turn their leaves yellow as an indicator that something is wrong with their environment.
6 Potential Reasons You Find Yellow Leaves on Roses
1. Fungal Diseases
One of the typical roses turn yellow is a fungal disease. You may notice small, round spots, colored red, purple or brown, on the leaves. There usually is yellow around the spots as well. Eventually, the yellow will spread across the entire leaf, leaving a lot of little holes. Unfortunately, if the fungal diseases continue, there will be large holes in your leaves.
Fungal diseases are prevalent in wet weather and moist environments. You may notice small, reddish spots on the bottom of the leaves, called rust. Sometimes, water has fungal spores which are why it is common in wetter areas.
How do you prevent fungal diseases in rose bushes? The first step is making sure your garden is sanitary. Remove old leaves and take off diseased canes in the winter. Pruning is best done in the spring because buds develop in then.
Another step to preventing disease is watering your bushes at the right time. You should always water early in the day. Your plant and the leaves will have plenty of time to dry before the cool nighttime. Some like to spray a fungicide in the early spring, or some use a lime sulfur in the late winter. However, natural prevention is the best route to preventing fungal diseases that cause yellow leaves on roses.
2. Not Enough Water
When it is hot outside, you may see your rose bush developing yellow leaves and wilting. The only way to prevent total shut down is to increase your watering significantly. If you fail to do so, your rose bush is likely to go dormant. Be sure to watch the weather! During humid days, the leaves can absorb extra water. On those days, you don’t want to overwater because it will lead to sopping, wet ground. Overwatering can result in fungal disease and other issues.
During the summer, spider mites can eat through the leaves of your rose bushes, as well as other plants. When they bite the leaves, they inject their saliva that leaves chlorotic spots. These spots cause the leaves to turn yellow slowly.
Spider mites are extremely tiny, but you should be able to see them on the underside of the leaves. You should check any leaf that appears dusty, stippled or yellow. Luckily, you can get rid of them with a few different methods. One thing to do is overhead water in the morning which can knock off spider mites. Miticide can be applied to help get rid of mites.
When you notice the yellow leaves on roses, check the soil moisture. You might have overwatered or have a few days in a row with rain. Lack of sunshine could lead to a problem as well, especially when coupled with an abundance of water. It will result in saturated soil. However, roses aren’t fond of that; they need soil that has plenty of oxygen movement. Saturated soil leads to water staying near the root zone for too long. You want land that irrigates well.
5. Lack of Proper Nutrients
To flourish, roses need the right nutrients to grow. If they don’t have enough nitrogen available, it can cause the leaves to turn yellow. In these cases, the remedy is simple. You need to purchase a well-balanced rose fertilizer in the stores. Always follow the directions on the bag; using too much fertilizer can lead to an overabundance of nitrogen. Too much nitrogen can cause an explosion of green leaves with very few blooms. You can also add kelp meal and alfalfa meal to your soil.
Changes in the weather can cause the yellowing of leaves. If the weather turns hot or cold, the rose bush can feel stressed, leading to yellow leaves. Heat stress is a common reason that leaves turn yellow and drop foliage. The plants do so to cool down during the heat. Also, if they are experiencing other stressors, heat will lead to an increase in yellowing.
Another problem could be radiant heating from the ground. During summer, the ground could absorb too much heat and radiate up the lower parts of the rose bush, causing the yellowing of the lower foliage. One way to reduce radiant heat is by using shredded cedar mulch or any light colored mulch instead of dark colored.
Treating Yellow Leaves on Roses
The treatment path is determined by the issue leading to the yellowing. First, it is important to keep your rose bush properly watered without overwatering it. You can purchase a moisture meter to determine if you need to water the plants or if it can wait. Always water your roses in the morning or the evening, especially during sunny days. Wet leaves can be burned by the hot sun.
Taking time to check the leaves and foliage of your plants is important. A thorough checking at least once a week can show if you have any pests. Finding them early on is the best way to prevent further damage. Another consideration is sunlight. Rose bushes do need around six hours of sunlight each day. If they don’t receive enough light, they will drop leaves to help survive. Make sure the area you chose to plant has plenty of sun and drains well.