Effects of winter climate on growth potential, carbohydrate content and cold hardiness of timothy (Phleum pratense L.) and red clover (Trifolium pratense L.)

altura carbohydrate content clima climat climate cold container planting contenido de carbohidratos cultivo protegido culture sous abri durcissement endurecimiento frio froid growth rate hardening hauteur height hiver invierno noruega norway phleum pratense plantation en container primavera printemps protected cultivation resistencia a la temperatura spring taux de croissance temperatura temperature temperature resistance teneur en glucides trifolium pratense variedades varieties weather winter