Ornamentals Produce Facts English

Description

Polianthes tuberosa. Spikes of ivory flowers much prized in the East for their fragrance and by western florists for accents and bridal bouquets, tuberose flowers bear as many as 50 florets, in pairs, on a tall spike. The postharvest life of these flowers typically is limited by failure of developing buds to open, so that the life is determined by the life of the flowers that were open at harvest. Proper pre-treatments can greatly extend the life of tuberose, and should routinely be carried out with flowers intended for storage and transport.

Quality Indices

The flowers are normally harvested with 2-4 open blooms on the spike. Although earlier harvest provides a spike that is more resistant to transportation, the buds are unlikely to open after transport unless properly pre-treated. Flowers for the local market may be harvested with more open flowers on the spike. It is unfortunately difficult to determine whether tuberose flowers have been effectively pre-treated prior to purchase. Look for straight stems, unblemished blooms, and work with your supplier to ensure that the flowers have been properly pretreated.

Grading and Bunching

Tuberose are sold in bunches of 10 stems.

Ethylene Sensitivity

Floret opening is reduced in spikes exposed to high concentrations of ethylene, but this effect is probably not normally of commercial significance, so 1-MCP or STS treatments are not warranted for tuberose.

Pretreatments

Tuberose flowers should be pulsed for 24 h at room temperature with a preservative solution augmented with 20% sucrose. This pretreatment will significantly improve vase life and opening of buds on the flower spikes. Flowers to be pre-treated in this way should preferably be harvested dry, graded, bunched, and re-cut, then placed immediately in the pulsing solution.

Storage Conditions

The optimal temperature for cooling and storage of tuberose is 0°C, but after only short periods of storage, the buds on the spike fail to open. Pulse pre-treatment with sucrose overcomes this problem, and after 6 days in storage the flowers open as well as freshly cut spikes.

Packing

Tuberose may be packed in hampers or in horizontal fiberboard boxes. If packed horizontal, they should be held at the proper temperature to avoid geotropic curvature.

Special Considerations

Florists often use individual tuberose blooms in corsages and boutonnieres. Proper pre-treatment of the spikes will ensure continued opening of the blooms in the florists’ workroom and consequent increased utility of each spike.

October 2004