One of our biggest floral crops is Tuberose - Polianthes tuberosa. Its incredible fragrance makes it one of our customers' favorites. It's easy to grow, outpaces almost all weeds, is quick and easy to cut, multiplies rapidly, and has almost no pest problems. We grow the single Mexican variety.
Six years ago, we bought 500 individual tubers. From that original purchase, we now have around 3000 clumps, each of which is has 4 to 8 tubers the size of the originals.
Tuberoses were grown in central North Carolina in the early 20th century for the fragrance industry, and they are grown extensively in India today for that purpose.
This time of year, we dig and divide them. They are supposedly winter-hardy in Zone 7, but we prefer to dig and divide to get maximum yield and not risk a really cold snap killing them. Sometimes we start digging before the first freeze, but most years we wait until about mid-November to dig them, after much of the foliage has begun to dry up.
We divide so each clump has 3 to 5 "large" tubers that will each make a flower next year. This is a "perfect" clump of three tubers.
We cut off the foliage, get as much dirt off as possible, and store them in bulb crates. We save "baby" tubers also. We plant them in the spring and they grow into flower-sized ones in one season.
We try to keep crated tubers in the sun for a few days to speed the drying out process. If it it's too cold for that, we put them in our garage with a fan running to keep the air moving around them. If they don't dry out thoroughly, there are a number of funguses that will quickly grow, particularly where the foliage has been cut off.
They happily remain crated until the following spring.
We plant them back in stages in the spring, although their daylength sensitivity makes them difficult to space out too much. Our first planting is around April 1, and these bloom August 1. a June 1 planting blooms around August 15, and a July 1 planting blooms around September 1. Each planting blooms over a two week period, with a few stragglers blooming for the rest of the summer.
They are great in wedding work, and for sale to retail customers. Two or three blooms can fill a room with their extraordinary fragrance.