The rose is considered the most acclaimed flower in the world. They are a classic symbol of love and romance and come in a variety of shapes, sizes, scents, and colors.
A common sight in gardens and houses, roses are perennials that are known for being easy to grow and care for. Nonetheless, they are still susceptible to getting yellow leaves.
This article lists the major types of yellowing that can occur in rose leaves, what they are a symptom of, and the steps you should take to fix it.
Why Do Rose Leaves Turn Yellow?
The green color of rose leaves has derived from the pigment in chlorophyll. Chlorophyll is responsible for absorbing sunlight, which the plant converts to energy to help with growth and maintenance, through a process called photosynthesis.
Leaves that do not have enough chlorophyll appear yellow in color instead of green. The technical term for this yellowing is called chlorosis. Chlorotic leaves are often one of the first signs something is not right with your plant.
There are many reasons your rose plants may be experiencing chlorosis. It could be from something as simple as overwatering to a lack of nutrients in the soil, to a disease.
Pinpointing the specific cause of chlorosis in roses can be difficult. Therefore, it is beneficial to identify additional symptoms alongside yellow leaves, to help identify the cause and ultimately rectify it.
Rose Leaves Turning Yellow and Falling Off in Summer
If your rose has yellow leaves that are falling off during the summer months, this is commonly a sign of overwatering. Too much water and poor drainage can lead to the soil becoming saturated with water.
When roses become waterlogged, the root system becomes devoid of oxygen and begins to “drown”. As such, they cannot fulfill their necessary function of delivering essential minerals and nutrients around the plant, including the leaves.
As a result, the leaves become yellow and drop off as the plant begins to die. Wet soil also provided the perfect conditions for a fungal infection called root rot to set in. Infected roots die, which also leads to yellow, falling foliage.
Rose Leaves Yellowing with Dry Brown Edges
A combination of yellow and brown leaves combined with dry, brittle edges suggests you have not given your rose enough water and it is undergoing drought stress.
Drought stress may be the result of not giving your rose enough water in the first place. Additionally, if it’s planted in fast-draining soil, it may not be retaining moisture, even if you are providing sufficient water.
Harsh sunlight or excessive heat directly at the base of your rose can increase evaporation from the soil. This evaporation may be further amplified if you have particularly dark mulch or sandy soil, causing the soil to quickly dry out.
Roses planted in containers or pots are also more prone to drought stress than those planted in beds. This is because pots often hold less soil and less moisture and can heat up fairly quickly.
Yellow Rose Leaves with Rust Patches
Yellow rose leaves accompanied by rust-colored patches are a clear indication of rose rust. A fungal disease that affects members of the rose family, including roses, hawthorns, apples, and pears.
This type of fungal infection is spread via airborne particles that carry on wind and rain.
Infected plants begin to show orange to yellow spots on their leaves in late spring. Which spreads quickly, causing the spots to spread and merge into solid patches of yellow across the whole leaf. It is accompanied by small rust-colored pustules on the underside of the leaves.
If left untreated, the infection will weaken the plant, and reduce its vigor and overall health. Therefore, it is essential to identify the rust’s early symptoms and take appropriate measures by treating affected plants with a fungal spray.
Rose Leaves Yellow and Curling
Yellow rose leaves combined with curling edges are usually a sign of nutrient deficiency, specifically nitrogen or iron deficiency.
Nitrogen is a vital component of chlorophyll, which is needed for photosynthesis, and leaves without adequate chlorophyll will develop chlorosis.
This vital macronutrient is also an important component of amino acids, which are used to build proteins. Without proteins, plants lack rigidity and structure, hence are prone to withering.
Iron deficiencies are often mistaken for nitrogen deficiencies as they show similar symptoms. Plants require iron to produce chlorophyll and assist in photosynthesis. The main difference is, the veins of an iron-deficient leaf will remain green, whilst the rest of it is yellow.
Yellow Marks or Patterns on Rose Leaves
Symptoms of mosaic leaf virus include yellow or light green mottling or streaks on the leaves. The leaves may also be distorted, stunted, or have dead patches, and the plant may produce fewer flowers or show signs of weaker growth.
Once a plant is infected with mosaic virus, there is no cure. The best way to prevent the spread of the mosaic virus is to practice good garden hygiene, including regularly sanitizing pruning equipment, and disposing of infected plant material.
To control mosaic virus, it’s essential to remove all infected leaves and dispose of them safely away from the garden. Aphids, which are common vectors of the virus, should also be controlled through natural or chemical means.
Yellow Rose Leaves with Black Spots and Fringed Edges
The appropriately named black spot fungus is most probably the reason your rose leaves are yellow with black or dark brown spotting. This fungal disease can be distinguished from others due to the fringing it causes around the edges of the leaf.
Black spot symptoms are caused by a fungus that develops under wet and humid environments. It spreads via infected leaves and as the disease progresses the leaves may eventually drop off.
How to Prevent Yellow Rose Leaves
Once you have figured out what is causing your rose plant to develop yellow leaves, you can focus on finding a solution. Below I have listed ways to reverse yellowing leaves and prevent future cases.
Overwatering
Generally, roses require around 2 inches of water every week. If your roses are planted outside, implementing a rain gauge can help you keep track of how much water they are receiving. Or simply push your finger an inch or two into the soil and if it’s damp your roses don’t need any further water. If you find the soil is often wet, then you may need to improve drainage.
If your roses are planted in clay soil with poor drainage, I recommend replanting them in soil with plenty of grit or sand. Alternatively, transfer them to a raised bed or pot with drainage holes.
Underwatering
The easiest way to save roses suffering from drought stress is to give them more water. Although deep watering once a week is usually sufficient, they will likely require more if the weather is particularly hot or arid.
The best way to water roses is with a drip irrigation system or to give them a thorough soaking by hand. Potted roses require extra attention as they are more prone to drought.
Heat Damage
Although direct sunlight is ideal for growing roses, if temperatures are above 85oF the plant can suffer from heat stress. In warmer regions, roses should be planted in areas that receive partial shade to avoid scorching the leaves.
Artificial shade can be created when necessary and they will likely require more water than usual to prevent heat stress.
Nutrient Deficiencies
To diagnose any nutritional deficiency, you must first conduct a soil test. Soil analysis kits can identify which nutrients are present in the soil, or soil pH.
Soil pH plays a fundamental role in the nutrient uptakes of roses and plants alike. Roses require a slightly acidic pH of between 5.5 and 6.5. If the pH is too alkaline, roses will struggle to absorb phosphorous, iron, and manganese, leading to deficiencies in these nutrients.
To make the soil more acidic, you can mix compost, mulch, coffee grounds, or sulfur into it. Additionally, if you know what specific nutrient your rose is deficient in, you can purchase a fertilizer rich in that element to give your plant.
Disease
When it comes to diseases, prevention is always the best method. Roses grown in optimal environmental conditions are fairly hard to diseases, but this doesn’t mean they are immune.
Unfortunately, if your roses develop black spot disease, there is no cure. You should remove infected roses to prevent the disease from spreading.
FAQ Rose Leaves Turning Yellow
Do rose leaves fall off naturally?
Roses are deciduous meaning they shed their leaves annually during late fall or early winter as part of their normal seasonal life cycle. Leaves shedding outside this period, however, is often a cause for concern.
You may also enjoy reading 17 Beautiful Flowers That Look Like Roses
Citations
- RHS – Black Spot Disease
- University of Arizona – Nutrient Deficiency (Nitrogen and Iron)
- The University of Missouri – Rose pH
Ben's horticultural interest grew when graduating from Hertfordshire University in 1997. Having contributed to numerous publications including Better Homes & Gardens, Garden Design Magazine, and The English Garden. He is also the author of Propagating Houseplants Made Easy.
