Mildew is a common fungal disease prevalent on roses growing in a warm and dry daytime climate and humid or rainy and cool overnight conditions. The fungal spores, known as Spathaerotheca pannosa, colonize on the leaves, young canes and flower heads, creating a white, dry film and contorting the foliage and flowers, eventually killing the tissues in very serious infestations. Mildew resistant roses are a specialty breeding category due to the prevalence of the disease.
John Cabot is a climber that flowers in classic red. The flowers are produced on sturdy and arching stems. It grows vigorously to reach 5 to 6 feet in spread and up to 10 feet in height at maturity.
'Captain Samuel Holland'
Captain Samuel Holland is a climbing rose that blooms in a deep pink hue with semi-double flower heads. It has no consistent fragrance and reaches 4 to 5 feet in spread and up to 6 feet in height at maturity.
Henry Kelsey is a mildew resistant climber that produces classic red roses with yellow center eyes. It is a lightly fragrant cultivar and has a continuous bloom season. Henry Kelsey reaches 6 feet in spread and 10 feet in height at maturity.
Louis Jolliet is a climber with medium pink flowers but no appreciable fragrance. It produces double petal blooms and is purported to be extremely cold hardy and resistant to mildew and other diseases. It is on the smaller side and reaches 5 feet in spread and height at maturity.