Rose bush leaves can turn yellow due to lack of water, spider mites or fungal diseases, such as blackspot and rust. Other symptoms are necessary to identify the exact cause of the yellowing.
When leaf yellowing is caused by lack of water, it is accompanied by wilting and shedding of leaves. This occurs mostly during hot, dry weather and can be remedied by watering the rose bush more. When a rose bush is infected by blackspot, the leaves develop small red, purple or brown spots with yellow outlines. With rust, some leaves may develop reddish spots on the underside, while others turn yellow and fall off. Spider mites pierce the leaves, leaving behind yellow spots, which eventually turn entire leaves yellow. Mites can be seen on the underside of the leaves.Learn More
Basil can turn yellow after it has fully matured or as a result of improper growing conditions. Typically, basil begins to naturally yellow after the plant has produced seeds.Full Answer >
According to the Missouri Botanical Garden, heat stress or fungal disease can lead to the yellowing of hosta. Scorch or heat stress leads to browning leaf margins and yellow areas between the main leaf veins. Fungal disease causes the base of the leaves to rot, which causes leaves to yellow.Full Answer >
Rose bush leaves can turn yellow when there is an issue with light, water, pests, disease, fertilizer or heat stress, according to Gardening Know How. After yellowing, the bush may lose the leaves entirely.Full Answer >
Cucumbers turn orange when they grow excessively ripe before harvesting, explains Veggie Gardener. The cucumbers first turn yellow, and if left on the vine, they quickly develop a vibrant orange hue. This happens because chlorophyll levels decrease past the point of peak ripeness. Orange cucumbers are very bitter and unsuitable for human consumption.Full Answer >