- 1). DISEASES
Black spot
Black spot is one of the most common rose diseases. Black and brown spots will appear on leaves, a growing ring of yellow gradually appearing around the dark spots, and the leaves will eventually fall off. Preventative measures for black spot include watering in the morning and avoiding getting water on rose bush foliage. You can make a preventative spray with baking soda and water. Treat black spot with a fungicide (there are many available that are specially formulates for rose care). - 2). Powdery Mildew
Powdery mildew is another common rose disease that leaves white or grat spots on leaves and causes leaf drop. It can also be prevented to some extent by careful watering practices. Spray baking soda mixture as a preventative, and treat powdery mildew with fungal spray. - 3). Rust
Rust will most often occur in damp, cool times of year. Reddish-orange bumps that appear on leaves signals the invasion of rust. Spray with lime sulphur or baking soda spray to check the disease; in some cases you will need to resort to strong fungicides. - 4). PESTS
Aphids
The number one pest of roses is aphids. Aphids are small, green creatures that suck sap from the leaves buds, and stems of roses; aphids are particularly fond of new growth. You can get rid of small quantities of the insects by spraying the affected areas with a stream of water. For more serious cases, use insecticidal soap or insecticides. - 5). Mites
Mites, small imperceptible creatures that leave webbing, stippled leaves, and leaf drop in their wake, are especially troublesome in the South. The water stream trick will work for small infestations. For bigger mite cases, though, pull out the miticide. - 6). Thrips
Thrips are small yellow or black creatures that feed on rose flowers. Prevention procedures include making sure rose bushes have enough space and air flow between them and that you remove spent blossoms quickly. Insecticides are often not helpful, so try spraying roses with water or insecticidal soap. - 7). Healthy roses require a good amount of care, but your efforts will be well repaid by the abundant and beautiful blooms your plants will produce.
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