REGIONAL DEVELOPMENT AND SPECIALIZATION OF GREENHOUSE HORTICULTURE IN THE ATSUMI PENINSULA, CENTRAL JAPAN

Abstract

In the Atsumi Peninsula where it is mild in winter there is a district where a great crop of Denshokiku (chrysanthemum cultivated in greenhouses with electric illumination) is raised in greenhouses. The main body of this tract runs along the Pacific coast of the peninsula for 20 kilometers, the area under greenhouse cultivation being estimated at 660, 000m2 in 1964. The conglomerational ratio of greenhouses in the tract shows to be the highest in Japan. The present paper has two aims in view; it has, in the first place, to explain the process of the development of this kind of horticulture, whereby to give light on the actual state of this greenhouse horticultural district; and it has also to consider the factors that have made the horticulture in question differentiate from one region to another in this district. The greenhouses there generally raise three harvests a year, the main crops being Denshokiku (cultivated by growth inhibition method), summer-time chrysanthemum (by intensive culture), melon and tomato. The use of a greenhouse is various as according to the order of rotating the crops mentioned, which culminates in the differentiation of the district into severval regions, each having its own peculiar features of this industry. There are four regional types of crop-raring, which are distributed among seven regions of this district. These four types are determined by the shipping time of the Denshokiku-crop. It is thought that since the greenhouse horticulture aims at forwarding to the market its crops raised both by intensive and inhibition methods, during the short period when the main agricultural crops are off season, the time for forwarding the horticultural harvests is varied from one region to another, to the result that a great many greenhouse conglomerates have been formed in this district. After analysing the management of the greenhouse horticulture in this district, it has been made clear that the factors causing the regional differentiation could be pursued in the reciprocal working of the three requisites; namely, the natural conditions of each region, the historical process of the development of horticulture there, and the compound management of agriculture in this district. The basis upon which the regional differentiation has been made is the natural conditions, such as the landform, soil, climate, etc. that are peculiar to the regions concerned. To be more concrete, these natural conditions are seen in such regional differences as the presence or non-presence of hills which may protect the crops from the cold winter monsoon, sandiness or non-sandiness of the soil in those regions, etc. By dint of such differences in the natural conditions this district has been historically differentiated into several regions, for instance a region favoured by the best coditions has been enabled to be stabilized as a horticulture area, and to select a forwarding time when the market price of the crop is the highest, till the region has been quite firmly established. Moreover, since the greenhouse horticulture is usually carried on in conjunction with other branches of agriculture, it can be thought that the regional differentiation in question has been promoted by the difference in the ways of managing agriculture that were in practice prior to the beginning of the greenhouse horticulture.