Abstract: The single and interactive effects of nitrogen supply and light conditions on Hosta 'Blue Umbrella' growth and photosynthetic characteristics were studied in this paper. The Hosta was cultivated with sands under four kinds of light conditions (100%,50%,30% and 10% of natural sunlight respectively) and four kinds of nitrogen supply (0,0.5,1.5 and 2.5 g·kg^-1 soil respectively).Results showed that biomass, growth characters, photosynthetic rate and soluble protein content increased at first and then decreased as light density decreased in the same nitrogen supply, the suitable light intensities for Hosta 'Blue Umbrella' were from 30% to 50% of natural sunlight. However, chlorophyll contents increased as light density decreased in the same nitrogen supply. In the different nitrogen supply, biomass, growth characters, photosynthetic characteristic, chlorophyll and soluble protein content increased firstly and then decreased as nitrogen supply increased, the suitable nitrogen supply for Hosta 'Blue Umbrella' was 0.5 g·kg^-1.

Key words: Hosta, Nitrogen, Light intensity, Interaction, Growth, Photosynthesis characteristics