Rosa 'MORten' (Linda Campbell)

Rosa 'MORten' (Linda Campbell) was bred by Ralph S. Moore in the United States and is a cross between Rosa 'Anytime' and R. rugosa 'Magnifica'. It was patented on April 13, 1993 and has patent number PP8,199. It is a hybrid rugosa rose.

In our area, we have noticed Rosa 'MORten' (Linda Campbell) facing problems from black spot (Diplocarpon rosae) and cercospora leaf spot (Cercospora rosicola) both common fungal problems that affects roses. We have observed that Rosa 'MORten' (Linda Campbell) still flowers well, despite black spot and cercospora leaf spot, as it is almost constantly in flower from spring until frost. However, due to its problems with black spot and cercospora leaf spot, it is often losing leaves and can appear sparse, making the overall appearance of the rose unattractive.

Black spot can cause leaves to develop black spots with blurred edges, yellowing leaves, and eventually partial or entire defoliation. While black spot is rarely fatal, it can weaken the rose by reducing its leaves and therefore its ability to photosynthesize. Although similar in appearance to cercospora leaf spot, black spot can be distinguished by the less defined and more feathered edges of the spots. As with many fungal problems, issues are generally worse in areas with high humidity. Black spot can be treated chemically.

Cercospora leaf spot can cause leaves to develop dark, maroon, purple, brown, or black spots with defined edges. Over time, the spots may age and turn brown or gray in the middle. As the disease persists, it will cause the leaves to turn yellow and eventually drop off the plant. While cercospora leaf spot is rarely fatal, it can weaken the rose by reducing its leaves and therefore its ability to photosynthesize. Although similar in appearance to black spot, cercospora leaf spot can be distinguished by the more defined edges of the spots. Also appearing similar to anthracnose, cercospora leaf spot can be distinguished by the time of year the disease occurs: cercospora leaf spot occurs during warmer months, such as in the summer, while anthracnose occurs during cooler months, such as in the spring. As with many fungal problems, issues are generally worse in areas with high humidity. Cercospora spot can be treated chemically.