I’m always looking for something highly fragrant to grow in containers over summer. Last year, I had big pots of beautiful acidanthera on the front porch and back deck, and they released sweet perfume near outdoor chairs and windows. This year, I’m going to try tuberoses (Polianthes tuberosa, Zone 7), popular as Victorian funeral blossoms. Their tall spikes of waxy white flowers produce one of the most intense floral scents; their essential oil is a primary ingredient in perfumery.
Tuberoses are tender perennials, growing from rhizomes that produce offsets each year. When grown in warm climates, they make use of the long growing season to spread in colonies. The combined perfume of a spreading tuberose patch must be overwhelming! In cold climates, the rhizomes can be started indoors in April, and will bloom in midsummer. (If started in May, expect blooms to start opening in August.)
The double tuberose (veseys.com) is sometimes listed with its cultivar name, ‘The Pearl’, and may be slightly less scented than the single species. That’s just guessing on my part, and if I can find both single- and double-flowering tubers, I’ll try both for a sniff test. The flower spikes rise and begin to enlarge their green buds over several weeks, each bud becoming white with a pale pink flush. When the buds begin opening from the bottom of the stem, the flowers are entirely milky white.
Each tuberose rhizome will produce grass-like, 18-inch (45-cm) leaves and flower spikes up to 24 inches (60 cm) tall, with two to five flower spikes from each rhizome (depending on the age and size of the rhizome). When planting in the ground or in pots, set rhizomes three inches (8 cm) deep, and space them six to eight inches (15 to 20 cm) apart.
In the fall, lift tuberose rhizomes before hard frost and store indoors over winter. If grown in containers, leave the rhizomes in the pots, cut down the spent flower spikes and foliage, and place the pots in loose, unsealed plastic bags in a cool basement. (They might need a little water mid-winter if the soil seems excessively dry.) Bring them out the following spring, and water regularly.
Using containers for perfumed plants lets me have deeply scented flowers close by, and I can cart pots off when the flowering period finishes. There’s a bit of economy in this method, as just a pot or two has quite an impact. If tuberose were planted in the garden, I would need more to pump up a scent cloud to float across the garden and reach me on the deck. Planting in pots also means there’s no damage from animals, weather, and soccer balls.