Vegetables gardens tested for Mars

Scientists from NASA hope that astronauts will grow their own food on the Red Planet. The journey to Mars could take two-and-a-half years and so they will need to take a lot of food with them. They will never be able to come back to Earth. This means they will need to grow their own fruit and vegetables on the planet. However there is a problem: Mars doesn't have soil that is good for growing things. For this reason, NASA has been testing "Martian gardens" to see what might grow on Mars. They used a soil made of crushed volcanic rock and so it's similar to the red dust on Mars. They grew lettuce in it. It tasted normal, but it had weaker roots and took longer to grow.