PROBLEM TO BE SOLVED: To promote growth of a leaf vegetable such as spinach and to clean up environment in cultivation of the leaf vegetable by adopting technique for soil cooling and by efficiently utilizing combustion gas.SOLUTION: According to structure in which a pipe 4 is buried in soil 1 for cultivating a vegetable 3 and which supplies cooling water to the pipe 4, soil is cooled to temperature suitable for growth of the vegetable and further dew condensation at the piping 4 for cooling water is utilized so that the irrigation amount can be reduced, which leads to economization. Besides, combustion gas, CO2, that a gas type device exhausts, blowing out from a side hole opened at a gas piping 5 on the soil 1 is supplied to the leaf of the vegetable 3 so that photosynthesis proceeds, promoting growth of the vegetable and thus high-quality and inexpensive vegetable can be provided, while by the combustion gas piping 5 also being cooled by the cooled soil 1, the combustion gas can be prevented from heating the soil 1 and from heating ambient air on the soil 1.【課題】ほうれん草のような葉野菜の栽培に土壌冷却の手法を採り、併せて燃焼ガスを有効利用することで、葉野菜の生育促進と環境浄化を図る。【解決手段】野菜３を栽培する土壌１の中にパイプ４を埋め込み、このパイプ４に冷却水を供給する構造によると、野菜の発育に適した土壌温に冷却され、しかも冷却水配管４の結露を利用して、灌水量を削減できるので、省力化される。また、土壌１上のガス配管５に開けた側孔から燃焼ガスが吹き出すことにより、ガス式の冷却装置から出る燃焼ガスすなわちＣＯ2 を、野菜３の葉に供給するので、光合成が進んで野菜の生育が促され、高品質で安価な野菜を提供できるが、土壌１の冷却で前記の燃焼ガス管５も冷却されるので、燃焼ガスで土壌１が加熱されたり土壌１上の大気が加熱されるのを防止できる。【選択図】図２
