Genus Polianthes Tuberosa, Family Agavaceae
Hardy in zones 8-10, otherwise grow as an annual.
Mid to late summer
Tuberose foliage has grassy foliage, similar in appearance to daylilies. Each stem can bear a dozen or more white blooms, which may remain closed if the heat is particularly stifling.
True to its agave heritage, the flowers are slightly waxy, offering protection against desiccation, but the blooms can still shrivel in direct sun when temperatures are 95 degrees F or greater. If this sounds typical of your summers, plant the bulbs where they will receive some afternoon shade.
- Plant them in soil with good drainage in a sunny location.
- Space the bulbs six inches apart, and cover them with two inches of soil.
- Make sure the bulbs get a weekly drink, either through rain or irrigation.
Although tuberoses need full sun to reach their blossoming potential, they don’t like to bake in parched soil. Keep your tuberoses moist with the help of a 3-inch mulch layer.
Tuberoses are moderate to heavy feeders. Apply a slow release granular fertilizer at the beginning of the season. A 5-10-5 fertilizer will provide the necessary phosphorus to encourage flowering.
At the end of the growing season in zones 6 and colder you’ll have to decide if you want to save your tuberose bulbs for next year. If so, dig them up, let them dry, and store them in a cool place.
- Single Mexican: Easiest to grow and earliest to bloom.
- Double Pearl: Every bit as fragrant as the single variety. Plants are shorter, flowers have blush tips, and blooms are fully double.