Even though the space industry is pacing forward with an unprecedentedly high speed, there are still certain limitations that stand in the way of space conquest and exploration. There are plenty of things we take for granted back on Earth, access to fresh plants included. Fortunately, with the latest advances in biotechnological development, growing plants in space is no longer a distant dream. Discover the most interesting facts about plants in space and achievements humanity has already accomplished, below.
Is it possible to grow a plant in space?
Yes, and major advances have already been made in this area, even though our road to success was quite long. The first seeds were launched into space in 1946 by Harvard University, but they did not survive. Later in the 1960s, the USSR tried to replicate this experiment, and some space-traveling space seeds returned to Earth undamaged. However, it took another 16 years before the first plant bore fruit in space in 1982.
Since then, scientists have managed to grow quite a lot of them on the International Space Station (ISS), i.e., rice, lettuce, garlic, radish, potato, and many other useful cultures. Many wonder how plants can grow without soil in space. In fact, lack of soil is not the biggest challenge for plants to grow in space. As it happens, the soil is not a must-have requirement for growth because it primarily acts as a source of useful minerals that nurture seeds. The same minerals can be delivered to sprouts through water via a plant-growing method called hydroponics. Water rich in nitrogen, potassium, and phosphorus can be an equally important medium for agricultural growth.
So, if lack of soil is not the chief obstacle, what is? According to Orbital Today space magazine, the primary challenges of growing plants on the ISS are lack of oxygen and low temperatures. Without proper temperatures and oxygen, plants would not be able to go through all the necessary stages of photosynthesis, which is why growing any plants on the ISS can only happen in isolated, carefully controlled environments.
Another challenge for agricultural growth is the lack of gravity. Its absence makes it difficult for a sprout to determine its growth direction, which interferes with normal seed development. Besides, microgravity affects the water circulation necessary for nurturing the seeds. Finally, most spacecraft today do not always have enough room for growing plants, which is another challenge that will have to be addressed eventually.
What plants grow best in space?
Today, we have NASA and other agencies successfully growing plenty of plants in space. Some of the most easily-cultivated examples include different types of lettuce, onions, cabbage, cucumbers, peas, and even wheat. So far, NASA has not been successful in growing fruit or trees. However, the abundance of available vegetables is already a major achievement; eventually, it should play a big part in our aerospace industry development because successfully growing plants in space can mean covering larger distances and maybe even colonizing other planets.
The last logical question is — do plants grow differently in space? The conditions for growing plants on the ISS are designed to closely replicate the environment back on Earth, so we do not have a definite answer to this question yet. However, scientists conducted a rather curious experiment back in 2018. Lunar Micro Ecosystem, aka little greenhouse on the Moon, is part of the Chinese Chang’e-4 spacecraft mission.
The spacecraft launched a sealed aluminum container to the Moon; this container carried different seeds, including potato, tomato, and silkworm eggs. The primary goal of this research mission was to determine if plants can independently produce oxygen in space. A year later, spacecraft cameras recorded several cotton sprouts, which indicates that space can be a welcoming environment for plants as long as we provide them with the necessary nutrients.
Potentially, the success of this experiment could mean building human habitats on the Moon and beyond. Right now, this may sound a bit far-fetched, but considering recent advances in technology development, very few things seem impossible at this point.
Of course, the list of plants that can be grown in space, is not as abundant as it is back on Earth. But if we think that growing plants in space has been next to impossible until very recently and commercial space travel was a dream, it becomes obvious how far we’ve already traveled. And there is no doubt now that space exploration will keep advancing in the years to come. So soon enough, we may see new plants growing in space.