ISHS Acta Horticulturae 109: III International Symposium on Flower Bulbs
ADVANCING AND RETARDING FLOWERING OF NARCISSUS TAZETTA GRAND SOLEIL D'OR |
| Author: | A.A. Tompsett |
| Abstract:
The economy of the Isles of Scilly is much dependent upon narcissus and in particular N. tazetta Grand Soleil d'Or. This normally flowers between mid January and mid February but there is considerable interest in advancing and retarding its growth in order to spread production, avoid depressing the market and in particular take advantage of high pre-Christmas prices. The Isles of Scilly sub-station is administered from Rosewarne Experimental Horticulture Station and since its establishment in 1967 has studied Soleil d'Or. Over the past ten years commercial systems for modifying flowering date have changed several times and hopefully will continue to evolve to the advantage of growers. Formerly, bulbs were lifted early, warm stored and replanted promptly for early flowering. An alternative, producing a lesser response, was to 'burn over' the ground with the bulbs in situ, using straw. More recently a combination of clear polyethylene sheeting covering the bulbs in the ground followed by burning over produced good results but has now been superseded by further developments. Currently, long term crops (unlifted for up to 6 years) are advanced by defoliating in late May and burning over several times each year using tractor mounted propane flame units. The method is simple, effective and a high level of flowering is maintained. Retarding is practiced less frequently but consists of using late planting, or with established plantations of covering the soil with clear polyethylene sheeting from July to October. Using a combination of advanced, natural and retarded crops growers can achieve a marketing period of 95 days (December - February inclusive) compared with the normal flowering period of Soleil d'Or of 34 days. | |
Download Adobe Acrobat Reader (free software to read PDF files) | |
