Of all the roses I planted in my backyard, the Poseidon is one of the most disease-resistant. No matter the amount of rain, when other roses start to gain white, powdery mildew, this beautiful rose always stays strong and healthy. It has no issues with black spots or any other diseases either, and I do not spray it with anything.
In 1990, the Kordes family, famous for rose breeding, decided that all garden roses should be naturally healthy and disease-resistant. They subsequently required all of their trial fields for garden roses to be managed and then evaluated without applying fungicides.
The Poseidon rose was bred by Tim-Herman Kordes, the fourth generation of the Kordes family, in 2004 in Germany. It was originally known by the name Novalis. Novalis is named after the pseudonym of poet Georg Philipp Friedrich Freiherr von Hardenberg (1772-1801). Later, Newflora LLC introduced it as Poseidon to the U.S. market.
Poseidon is a bushy, upright shrub rose with repeat blooms. This vigorous, floribunda rose has cup-shaped flowers that grow in flushes throughout the season.
It was a gold medal German ADR rose trial winner in 2013. Rose breeders often describe this trial as among the most challenging in the world. In ADR, trial roses are tested over three years, and the criteria analyzed include disease resistance, hardiness and attractiveness. Since 1997, no chemical pesticides have been allowed in this competition.
Poseidon shrubs can reach up to 5 feet tall by 2.5 feet wide. They have gorgeous and smoky purple-mauve buds that bloom into silvery, purple-ruffled delights. The bloom is fully petaled and the edges of the petals seem to be almost scalloped.
This lavender rose displays very full flowers with approximately 60 petals that are approximately 4 inches in diameter. I love its light-purple color, which gives the flower its uniqueness and rare beauty. Poseidon roses have mild, fruity fragrances, yet a long vase life. These gorgeous roses are perfect for making a bouquet at home.
Nevertheless, I have to point out that this vigorous beauty does not like very hot weather. When the sun is strong, it can burn and “fry” the flowers. In the Bay Area, it is better to plant in partial shade for best color. I have two Poseidons in my backyard. One is in partial shade, and it grows just like it should. The other is in the corner of a fence, and it reaches 6 feet outside the fence. Both are quite healthy and without any disease issues.
Michelle Isaac is a gardener in Los Altos. For more information, email [email protected] Julia Isaac contributed to this column.