Active during: Summer
Common Name: Tuberose
Type: Tuber; deciduous; summer-growing, winter-dormant; flowers in midsummer; popular cut flower.
Origin: species from Mexico.
Only the cultivar form of P. tuberosa, called the Pearl, is commonly grown and generally available. Tuberosa have a dense cylinder of waxy white flowers, packed along the top of a stout stem, about 1m tall. The blooms are very strongly scented, with a heady, almost overpowering perfume.
Tuberosa look their best in groups of 10 to 20 in the middle level of the mixed herbaceous border. The tubers should be planted in early spring, in soil loosened to a depth of about 20cm.Incorporate enough compost to make the soil loose, friable and porous. Plant the tubers with the pointed ends upward, with about 5cm of soil covering them and space them 10cm apart. Tuberosa do best in full sun, although they will also bloom well in partial shade.
Although frost will kill the above-ground parts of tuberosa, the tubers are quite safe underground in our climatic conditions. Water tuberosa regularly and deeply throughout spring and summer. Feed them periodically with old farmyard manure. The tubers may also be lifted at the onset of dormancy in early winter and kept out of the soil. Offsets form readily, so you can easily increase your stock by breaking these off when lifting the tubers.