Growing plants in space provides all sorts of challenges that we don’t experience here on earth. For a start the lack of gravity there is no up or down so the plant does not know which way to point its roots and stem. Soil is contained in plant pillows and the seed is glued to a wick which is inserted into the pillow. The pillows have to be tied down to stop them floating away. But after all this the astronauts were able to munch one or two leaves each. This information comes from Saturnineaqua at Tumblr.

Space Gardening 101

nasa:

You can?t escape eating (or gardening!) your vegetables, even if you?re in space. On Aug. 10, astronauts on the International Space Station sampled their first space grown salad. This freshly harvest red romaine lettuce was grown in the ?Veggie? plant growth chamber that is designed to make gardens flourish in weightlessness.

In a weightless environment, there is no up and down, so roots grow in all directions. Water and soil, the materials used to anchor these plants and allow for root growth tend to float away.

How Do We Grow Plants in Space?

1. Plant Pillows

The Veggie chamber helps solve the problems of a weightless environment by using ?plant pillows?, sounds comfy right? These pillows are bags filled with material for growing plants in space.
2. Wicks

Wicks are implanted into the bags and are used to draw water from inside the pillow to the plant.

These wicks also provide a place to glue the seeds. It?s important to orient the seeds so roots will grow ?down?, and shoots that emerge will push out of the bag
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