Yes, there are plants in Antarctica today. They are mostly lichen, but in the past Antarctica is believed to have been covered with more complex plant species. This article talks about how giant flowers known as megaherbs found on Australia and New Zealand's sub-Antarctic islands are probably survivors of the same species that covered Antarctica before the last ice age 2 million years ago. These plants are believed to have started in Antarctica and spread to the sub-Antarctic islands where they remain today. The same species in Antarctica, of course, cannot survive in the current conditions on the continent, which first became inhospitable for these plants about 1.8 million years ago. They are still not entirely sure about the method of being transported to the sub-Antarctic islands, but could have been seabirds carrying the seeds in their feathers.