The main objective was to set up models of the soil-plant-atmosphere system for the growing of Grape Leaves with drip irrigation in the Binh Thuan Province, Vietnam. The computer software tool CoupModel was used in this modelling process. The focus of the model was the systems soil hydraulics and the water balance between its components. When running several 21 years simulations it could be seen that slight variations in soil texture inputs resulted in relatively big output changes. For example, by either using the soil texture laboratory results or the soil water retention inputs gained from tensiometers and moisture meters in the field, gave an annual irrigation amount difference of 100 mm. However, it can be questioned if the models reached the goal of simulating an  efficient irrigation schedule  due to the soil evaporation output being high throughout the year.  For further research, longer time series of field measurements together with more knowledge about the plant would be preferable in order to validate and improve the model. / MÂlet med denna studie var att uppr‰tta modeller ˆver mark-v‰xt-atmosf‰r-systemet i programmet CoupModel. Modellerna skulle anpassas fˆr odlingen av vinblad med hj‰lp av droppbevattning i Binh Thuan-provinsen i Vietnam. Fokus i denna studie var vattenflˆden och vattenbalansen mellan systemets komponenter. Efter att ha kˆrt flera 21 Âr lÂnga simuleringar var det tydligt att sm variationer i indata resulterade i relativt stora skillnader i utdata. Om till exempel  v‰rden  angÂende jordartens struktur  erhÂllna  frÂn laboratoriet anv‰ndes ist‰llet fˆr f‰ltm‰tningar frÂn tensiometrar och fuktm‰tare blev det en Ârlig bevattningsskillnad p 100 mm. Det kan ifrÂgas‰ttas huruvida mÂlet att simulera en vatteneffektiv bevattning blev nÂtt d jordavdunstningen var hˆg Âret runt. Fˆr vidare studier skulle l‰ngre tidsserier av f‰ltm‰tningar tillsammans med mer kunskap om plantan vara nyttigt fˆr att kunna validera och fˆrb‰ttra modellen.