Four more problems that affect roses

Rose rust

Look out for orange or black pustules on leaves and stems. Most of the modern roses are resistant to rust.

Powdery mildew

This fungal disease tends to be worse in high humidity and in plants where air movement is poor.

Aphids

Aphids suck sap from leaves and stems and secrete sticky honeydew, which encourages the growth of sooty moulds.

Rose sawfly

The caterpillars of the rose sawfly will eat the leaves of roses, sometimes completely defoliating a plant.