It turns out that your question is also on the mind of NASA who has given a lot of money to a scientist named Rob Ferl at the University of Florida to study just this question. He is interested in creating ecosystem on mars made up of plants, microbes and of course humans that will be able to survive in Mars's harsh environment.

Currently they are genetically engineering mustard plants that they can grow in small greenhouses on Mars. The genetics allows the scientists to tell how well the plants are surviving under different Mars like conditions including types of soil, water sources and air chemistry that they will encounter on the planet.

The way it works is, if the plant glows green it is stressed, if it does not glow, then it is doing well. How do they do this!!!??? They insert a gene from a jellyfish that glows in the ocean. Whenever the plant is stressed it will turn on it's jellyfish gene and glow green! Pretty cool.

So to answer your question is, yes! Scientists are trying very hard to get plants to grow on Mars, so that within 100 years we will be able to survive there. In fact, Robs glowing mustard plants are going on the next trip to Mars in 2007!

Here is a link to the work Prof. Ferl is doing about plants in space at the University of Florida.