I always get excited about new plants, especially if they promise a significant improvement over what is presently available. I wrote about the traditional tuberose a few posts ago and said that I was waiting for my three coloured cultivars to open. Well, they are in the polytunnel and, what with the cooler weather, growth has come to a standstill. I need to bring them into the house to keep them growing and stand any chance of seeing the flowers. But one has bloomed. I have grown some of these coloured tuberose before but made an effort to grow the three commonly available cultivars this year. Before I comment on my plants, a little history is necessary.
Although gardeners are only really aware of the common tuberose (Polianthes tuberosa), there are 14 other species. And unlike the common tuberose, which has never been found in the wild and has white flowers, the other species are found wild in Central America and have flowers with red, orange or striped flowers. The common tuberose is known in three forms, with single, semi-double and fully double (‘The Pearl’) flowers though I have found all three in the batches of ‘bulbs’ that I have bought over time. The plant is day neutral and will bloom whenever the plants are big enough to produce a flower scape. The fact that other species have different colours must have tempted people to try to hybridise them.
The first hybrids seem to have been produced in 1911, crossing P. geminiflora and P. tuberosa – named P. x blissi ‘Worsley Hybrid’. Then in 1980 Verhoek-Williams produced a hybrid and the Texan Bundrant, produced three hybrids. This is all very confusing since not just polianthes were used in the crosses but manfreda, a closely allied genus, too. But as these are all moved to agave now, including polianthes, the crosses are not as wide as previously considered.
Someone called Howard repeated the cross that made P. x blissi and this had pink flowers and was fragrant and called P. x howardii. Bundrandt crossed this with P. tuberosa to create P. x bundrandtii. To cut a long story short, the progeny were variously coloured with pink, red or maroon and had fragrance. Work has continued in China, Taiwan and Japan as well as the USA in the past few decades, based on P. x howardii and now there are many cultivars in various colours.
Taipei University (Taiwan) produced an important breakthrough with ‘Pink Sensation’ (which has not bloomed for me yet, though there is a flower scape) and it was introduced, by Ludwig and Co. (The Netherlands) in 2014.
Anyway, back to the present. ‘Super Gold’ is the first of my coloured tuberose to bloom. And I am at a bit of a loss to say anything nice about it. It is yellow but not that deep in colour and the shrivelling flowers do not drop off. The flowers are single and the petals do not spread much, though that may be down to cool temperatures. But worse, the flowers do not have a lot of fragrance. They do smell but, unlike its white relative, they do not fill a room with perfume – you have to get up and shove your nose in the flowers to get a hint of fragrance. I assume that, in warmer climes, the fragrance is stronger and, since these are bred as cut flowers, a slight scent is an advantage and not as overpowering in a bunch.
But I am rather underwhelmed. There are two more to bloom yet but I think I like my tuberose white and powerfully scented for now.
- Information from ‘Breeding of ornamentals: tuberose by S K Datta 2017