Antarctic plants fight extreme conditions. They have to struggle against the icy grip of Antarctica. Water is scarce. There is ice and snow as far as the eye can see, but no water. The ice and snow doesn't become physically available to the plants until it has melted. The air is dry, and evaporation, the loss of water from the plants to the air, is a daily danger.
There is hardly any suitable soil for the plant to put down its roots- Antarctica being a continent of rock and ice. The occasional crack in the rock may be filled with humus and guano. Humus is formed by the decay of dead plants and guano is the dropping of seabirds. This is rich in nutrients, but is thin on the ground. This is the home for the plants of Antarctica.