Potatoes on Mars is the first half of the fifty-first episode of Ready Jet Go!
Jet is fascinated by the Earthie potatoes that the kids have grown in the backyard garden. Now he wants to try to grow potatoes on Mars! They take several plants to Mars and try, but learn that potatoes need the right air, temperature, water, and even the right soil.
The kids are in the backyard, tending to a garden. Jet is lying in the garden and says that "potato" is one of his favorite Earth words and things. The kids discuss all the kinds of food that can be made with potatoes. Jet wants the actual potatoes to show up. Mindy explains that they grow down in the dirt. Mindy then finds a potato. Sean explains that he's been reading about the plan to send humans to Mars someday. Mindy asks how that's relevant to the current topic. Sean says that if humans are going to survive on Mars, they'll have to grow their own food, otherwise they'd have to bring all our food from Earth. Sean says that it's good that he's learning how to grow his own food, since he may have to do that on Mars someday.
Mindy asks if the astronauts will plant a garden. Sean explains that Earth plants would have a hard time growing on Mars since it gets super cold on Mars every night. Jet loves the idea of comparing Earth and Mars gardens. Jet wants to go there. Sydney and Mindy also want to go. Sean protests, because they don't know what Martian soil is like. Jet says that they're going to go there to find out. Sean still protests, but then Jet persuades Sean into complying with a rock ballad, "Potatoes on Mars". Sean ends up agreeing to go, and Celery pulls in with the wagon. As they all get in, Mindy remarks that this is her first time going to Mars. Sean protests that Mindy hasn't been downtown either, but he gets interrupted by the Takeoff! song and they all blast off into space.
They land on Mars, and Sean reminds the gang that they have a ticking clock. Jet notices that Sunspot has gone missing, so he and the rest of the gang call out for him. Sunspot appears, playing an electric guitar. He and his two plants are riding on Boop the rover. Jet communicates with Boop about their plan to grow potatoes on Mars. Boop falls over "laughing". The kids are confused, but Jet explains that Boop said that there's no atmosphere on Mars, and it gets really cold, too.
Later, Sydney notices that two of the potato plants have already wilted. Celery says that this is because it's too cold, and there's not enough air to breathe. However, the gang is breathing okay, because they have space helmets. They then rush inside the saucer so the plants can get some air. Even though Sean remarks that the experiment didn't go hot, Jet thinks it was great because of what they learned. Sean still wonders how future astronauts will grow their own food on Mars. Sydney comes up with an idea: they can build a greenhouse for the potato plants, and she explains what greenhouses are.
The group gathers some blocks and they start building a greenhouse. Then, they start to sing "Get Growin'". They enter the greenhouse and breathe the air. Sean says that next, they have to plant the potato plants in the Martian soil. Some of the plants are kept in the Earth soil, while some are put into the Martian soil. After Sydney waters a plant, she notices that the plants are wilting again. Sean scoops up some Martian soil and takes it back to his mini-lab in the saucer for an analysis.
Sean analyzes the soil and concludes that it is different from that of Earth since it is saltier. Jet is surprised to find out that Earth plants don't like growing in Martian soil. Jet says that he feels for the potatoes, and starts singing "Potato Changes". When the song ends, the gang boards the saucer to go home.
Jet wonders if there could be life on Mars. Celery remarks that the potatoes would be happier on Earth. Jet then starts to sing a reprise of "Potatoes on Mars", with Sean drumming, Sydney playing the piano, Mindy playing the flugelhorn, and Sunspot playing the guitar. The end.
- This marks the first time that Mindy gets to go to Mars.
- The plot of the kids trying to grow potatoes on Mars is a reference to the 2015 film The Martian.
- The song featured in the episodes is set to the tune of "Life on Mars?" by David Bowie.
- This marks the second time that Sean mentions that he sings in the shower, the first time being in Holidays in Boxwood Terrace.
- It is revealed that Sean and Sydney plays the drums and piano respectively.