Rome, “The Eternal City,” has such an ancient history, even the city’s plants have an exalted place. A 17th century folio documents rare and exotic plants in the Farnese Gardens. The close ties between the Farnese family and the Jesuits enabled the family to obtain exotic plant species from faraway places brought back to Rome by Jesuit priests. The folio includes the Spanish dagger, the passion flower and the cassia tree, among other exotic plants.
Yucca gloriosa, commonly called Spanish dagger, palm lily and mound-lily yucca, is an evergreen, single or multi-trunked shrub plant that usually grows to about 10 feet high with a spread of about 8 feet. The bright green leaves are between 2 and 3 feet long, ending in points, from a basal rosette. A terminal spike as much as 6 to 8 feet long rises from the middle of the plant, which blooms in the late summer, exhibiting purple-tinged, white, bell-shaped and fragrant flowers. The Spanish dagger does well in full sun though it tolerates partial shade, but what is most important is regular watering and well-drained soil. The Spanish dagger is a member of the Agavaceae family.
The passion flower or passiflora (Flos passionis) arrived in Rome during the 17th century, thanks to the efforts of Spanish priests in South America where it originates. In Spanish, this beautiful flower was called “La Flor de las Cinco Llagas” which means “The Flower With the Five Wounds.” In 1609, a churchman in Rome named Giacomo Bosio interpreted the drawings and dried plants he received for study. “Passionis” defines the suffering of Jesus Christ on the cross, and different parts of the passion flower symbolize various elements of the Crucifixion. For example, the five petals and five sepals represent the 10 disciples other than Peter and Judas, while the corona filaments stand for the crown of thorns. There are several hundred species of passion flower worldwide, although when Linnaeus officially classified the Passiflora in 1745, there were just 22 known species. P. incarnata is the species favored for medicinal uses, according to the Passiflora Online website.
The cassia or golden shower tree (Cassia fistula) is an evergreen tree with clusters of bright yellow, 3-inch blooms. The tree grows to heights of between 30 and 40 feet. The yellow flowers of this showy ornamental are the national flower of Thailand. The golden shower tree does best in full sun and well-drained soil. It is drought- and salt-tolerant but it cannot survive frost. The golden shower tree is a member of the Caesalpiniaceae family.