To enlarge the palette of environmentally-responsible landscape plants, 117 garden rose cultivars were evaluated under minimal input conditions. Other than mulching and irrigation, no other inputs were provided, including no fertilization and no pesticide applications. Plants were established in completely randomized blocks with four reps in the spring of 1998 with data collection beginning in 2000 and continued through 2002. Data on overall performance (an index comprised of flower number, percent of plant covered with flowers and plant growth) and relative chlorophyll content were collected the first and third week of each month from April through October. Disease ratings or incidence ratings were collected for Diplocarpon rosae Wolf (black spot), Alternaria sp. (petal blight) and Sphaerotheca pannosa (powdery mildew). Statistical analysis was performed on the mean data for all dates. `Knockout' was the top rose for overall quality with little or no disease observed, high foliage quality, and continuous flowers from spring until late in the fall. `Knockout' also ranked among the top rose cultivars in terms of overall nutrient concentrations (N, P, K, and Fe) in new growth tissue. Most of the hybrid tea roses such as `Peace' and `Double Delight' died in at least three blocks due to disease and a lack of vigor.

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