H.D. Hartmann
In addition to cauliflower, lettuce of butterhead type is one of those horticultural intensive crops favoured by the consumer all the year. Regarding outdoor-lettuce it has often been observed, however, that during May and June prices are falling suddenly, because during this period approximately half of the total annual production is put on the market. It is recommendable therefore to graduate planting in such a way, that the risk for the grower will diminish and to deliver lettuce continuously to market from the middle of May until October/November. This will be very important especially for those growers having contracts with supermarkets. Some papers concerning a continuous supply of lettuce have been published recently for Hamburg (H. Buhr and U. Paulsen, 1961), for the Upper-Rhine region (H. Süssbrich, 1963) and for Munich (E. Niller, 1965), as well as a number of theoretical calculations by W. Rothenburger (1966). Regarding South-West Germany with its centres in Baden-Wurtemberg, Rhineland-Pfalz and Hessen no particulars are at hand until now. In order to give useful recommendations to the mentioned regions, a number of studies has been carried out in Geisenheim/Rhine from 1965 until 1967.
Hartmann, H.D. (1973). TIMING OUTDOOR HEAD-LETTUCE IN S. W. GERMANY. Acta Hortic. 27, 72-76
DOI: 10.17660/ActaHortic.1973.27.7

Acta Horticulturae