Mars Exchange
Food for Mars Q&A with Wieger Wamelink - Part 1

Food for Mars Q&A with Wieger Wamelink - Part 1

by Natasha Schön on Thursday, 18th February 2016 in Food for Mars, People, Wieger Wamelink

In the past year we have introduced Food for Mars, a blog series about experiments conducted by a team of ecologists and crop scientists of Wageningen UR. The goal of these experiments is a proof of concepts for providing the first (human) Martians with ‘own-grown’ fresh food. These posts have sparked a lot curiosity, which is why we asked what questions you have surrounding about growing food on Mars. We gathered your input and posed your questions to Wieger Wamelink, a Senior Ecologist at Alterra. Here are the first set of top questions and his answers!

What are the possible difficulties crews will encounter? - Alex Lacki

There are many challenges, I will confine this to growing crops. The biggest problem in the end will be energy. Everything we will do over there will require a lot of energy and since the Sun, the source of energy, is farther away than it is on Earth it will be more difficult than over here. Growing crops will need energy for heating and light. In our design, the growth chambers will be below ground with at least 1.5m of sand to protect the plants from the galactic radiation. For now I do not believe in aboveground domes. There is no material thick and strong enough to build domes that are strong enough, that will allow visible light to pass, and block all the cosmic radiation. Building the below ground shelters, also for the human Martians, will be a major challenge. Another major challenge and one we are working on, is building a sustainable ecosystem that can support a sustainable crop growth. In our view that includes fungi, bacteria, and pollinators. From the bacteria and fungi we want only the good ones and not the pests. I see this as our biggest challenge.

What kind of food will be grown? Possibly plants from the colder climates, in order to not waste energy on heating the greenhouse? - Alex Lacki

The heating will probably not be a problem, which means we will not be limited to species from colder climates. We will set up a healthy diet but this will also be limited, since we will look at the energy and essential mineral and vitamin content combined with the growth efficiency. E.g. the potato (the real super food) for energy.

There will most likely be foods that the crews will have to live without for the rest of their lives. No pineapples bananas and strawberries for the rest of their lives? - Alex Lacki

I partly agree. The first settlers will have a limited diet. However, in principle there is no limit to the amount of crops that could be grown, providing they are willing to spend the energy to do so. Even small trees could be possible, there are nowadays even cherry trees available that give fruits when they are only 1.5m high (I have got them in my garden).

How will the harmful radiation like UV and cosmic rays be screened out? Is it possible to get sunlight in while keeping these rays out? - Duncan McPherson

This is a major question and problem. As stated above, I am not aware of a system that will filter out the harmful cosmic radiation. Moreover, as far as I understood from Professor Gerard’t Hooft, a Mars One ambassador, it is not physically possible to build a dome like this that is strong enough. That is why we aim to build chambers underground with a total controlled environment and led-lights and energy from solar panels. Therefore, I do not agree with many artist impressions that portray living quarters above ground, which includes The Martian.

Are the plants going to be grown IN Mars' soil? If not, and they are going to use Earth soil, isn't it going to eventually become spent? If so, what are the options on rejuvenating it? - Monie Brooks

My project is about growing plants in Martian soil. However, I believe that it is safer to use different ways of cultivating crops. I would include substrate culture and water culture as well. Bringing soil from Earth is not on that list, since it would contain not only wanted bacteria and fungi, but also the unwanted ones that could make plants and humans sick. Of course, the soil may be sterilised, but then there is almost no benefit left of bringing soil from Earth. It may contain organic matter and nutrients, but that can easily be added to Martian soil. No matter what, soils always need to recover from nutrient depletion and, on Earth, it also needs to recover from diseases or the lack of wanted soil life due to agricultural practises. On Mars, the soil will not have to recover from diseases, but it still needs to be manured etc.

I have noticed a lackluster to the plants, have seen other plants/flowers showing the same distinction, less color, less liveliness, is it due to not having the real sun' rays? - Monie Brooks

This is true and could be caused by several things. First, I used trays in the 2015 experiment, with ten different species in it. That is not ideal and the plants would have been competing for each other, for nutrients and for light, which causes less healthy plants to grow. Moreover, I do not have the glasshouse alone, and sometimes diseases come in, as we have seen in the 2015 experiment. The light itself should be sufficient, and when there is not enough solar light the lamps go on for additional photons. The lights are special growth lights.

Hi there - I'm a novelist and my latest book is set on Mars. So what are the key additives an astronaut would need to put in Martian soil in order to grow food? - John Kirk

Martian soil is sterile, there is no life in it (as far as we know, it is still under investigation, but I will talk about it as if there is no life). What I need are bacteria for the mineralisation of organic matter and the binding of nitrogen (N) and transformation into nitrate (NO3). Then I need fungi that would help plants with the uptake of nutrients. They live in symbiosis with the plants and enlarge the root system of the plant. There is no organic matter in the Martian soil, thus that has to be added, which can be done by using the feces of the human Martians. These feces serve as manure, as does the urine. The urine can be applied straight away, the feces have to be sterilised first because of unwanted bacteria that are present inside the human body. Above ground I will need insects for the pollination of the flowers. I would prefer bumble bees more than bees, since the first are easier to transport for a long period. The queen is the only one needed and probably could be in hibernation for half a year and they are better at withstanding unideal circumstances in growth chambers. If you would like more information, do not hesitate to contact me.

What measures will be taken to avoid contamination of Mars outside the colony by Earth organisms? I believe rovers are not allowed anywhere near liquid water. Surely that means growing Earth plants in Martian soil would need strict isolation protocols. - Mike Howells

This is an ethical issue and not for me to decide. However, contamination of Mars is an issue and if we grow plants there it may happen. The threat does not come from the plants themselves, since they will not be able to survive the temperatures, the atmosphere, and the devastating cosmic radiation. The problem may be caused by bacteria and fungi, but this will only happen if they survive these circumstances and there may sometimes be a very short period that liquid water is available (essential for all life). But I do not believe that even the toughest bacteria will be able to survive this. Nevertheless, bacteria have often surprised us, so we can not rule it out totally. Growth of plants therefore will be done indoors in closed and isolated rooms and no waste may be brought outside. However, as we know from Earth nothing is totally protected and when we stay there longer and with more and more people it is inevitable that sometimes Earth life will escape to the Martian surface. The question is, do we accept that?

Thank you all for all your interesting questions, for more questions and answers, also see Food for Mars Q&A with Wieger Wamelink - Part 2

Feel free to contact me, e.g. via the facebook page or the blog.

Greetings (or groetjes),


Dr. ir. G.W.W. Wamelink
Senior ecologist
Alterra P.O. box 47
6700 AA Wageningen
The Netherlands

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