Glossary

Anthracnose: One of the leaf spot diseases of roses. A tentative identification of anthracnose on leaves of 'Constance Spry':

Nursery Bands: Many mail-order nurseries grow own root roses (rooted cuttings) in 6" deep pots called bands. These specialized pots are commonly used in the plant trade for growing tree seedlings. The pots help the plants to develop strong root masses and are an optimal size for shipping and transplanting. Below is an example of a nice specimen that I received from one of my favorite suppliers:

Blackspot: The most pestilent of the diseases that affect roses on Long Island. The disease can be managed by growing blackspot-resistant cultivars. A photo of blackspot:

Different manifestations or patterns of spotting may be symptoms of either black spot or some other leaf spot disease (or a combination of several), including cercospora and anthracnose. The following spotting was found on the leaves of 'Eden':

So there are other leaf spot diseases of roses, but none are as debilitating as blackspot. The following leaf spotting is commonly found on certain old garden roses:

If you have an identification for any of the diseases pictured above, please email me.

Blackspot-Resistant: In my garden, roses that show very little or no susceptibility to blackspot and other leaf spot diseases. The rose should maintain clean and abundant foliage throughout the growing season and never lose more than 1/3 of its foliage. Because incidence of blackspot can vary from year to year, a rose is rated based on its cumulative performance in past years with weight given to the most recent years including the current season.

Cercospora: One of the leaf spot diseases of roses.

Disease-Free: A rose that shows little or no susceptibility to any of the major diseases of roses, including blackspot, powdery mildew, and rust.

Established:

Landscaping Roses: Roses that maintain an attractive appearance throughout the growing season, whether in or out of bloom. The growth habit must be conducive to many practical uses in the gardening landscape. The rose should be healthy and show little or no susceptibility to disease.

Organic: Roses that are rated suitable for organic culture on Long Island should show excellent resilience and disease-resistance without the use of harmful or inorganic pesticides. If the rose defoliates, it should releaf quickly and/or maintain at least 1/3 foliage throughout the growing season. It must be robust and healthy, and able to bounce back from stress. It should thrive on minimal garden care, and once established it should improve or maintain its vigor for many years.

Powdery Mildew: One of the major diseases of roses, but a relatively minor problem for roses on Long Island. Certain cultivars, particularly gallicas, are susceptible -- especially in dry shade. Severe outbreaks can stunt and defoliate roses if left untreated. Powdery mildew is easily eradicated with a single application of Vapor Gard. Preemptive spraying is entirely unnecessary.