Hi all, I was just wondering about the possibilities of how well plants could grow on Mars and type of plants that could be most ideal for the harsh conditions on Mars? of course they would need to be growing in a greenhouse with good soil. This has always interested me.

I'm thinking something like a hybrid cacti plant could grow on mars that requires little water that will grow in a cold climate with 1% atmosphere.

You would have to provide an atmosphere (nothing will grow in the atmospere of Mars), warmth, a light source, water and everything that Martian soil doesn't have. What Martian soil does have is a lot of nutrients but what it doesn't have is all the bacteria that makes soil alive.

With a sealed greenhouse, an artificial atmospere, a light and heat source, water and bacteria, you could grow anything you wanted.

The only thing that Mars has going for it is nutrient rich soil.

when are you going to Mars ???

I'm not going to Mars anytime soon, but I think the topic of growing plants on Mars is certainly an interesting subject. The ISS International Space Station have grown plants in zero gravity which look pretty interesting... they have also flowered plants on the ISS as well.

What is the point? There is no life on Mars of any kind except when humans set foot there and walk around in their space suits.

But if people did decide to colonize Mars, they would need to grow something to eat. The grocery would be a long drive...

WillC said:What is the point? There is no life on Mars of any kind except when humans set foot there and walk around in their space suits.

There is always a point to a point... I know it will be a while before anybody goes to Mars but I think the research and experimentation is very important not just for growing plants on Mars but for other things as well like underground farming and things like that.

My guess is that we will perfect closed ecosystems for space craft and space stations or habitats on the Moon and asteroids before we terraform Mars enough for anything other than lichens to grow. Whatever greenhouse system fed them during the trip to Mars would continue to feed them on the surface (that's my guess, anyway).

I would also guess that any higher plants from Earth would need a lot of breeding or gene-engineering to endure Mars' natural temperatures (-70 °F average, 70 °F to −240 °F extremes), extreme dryness and near-vacuum (and what little air they have is almost oxygen-free).

Inside a greenhouse, at least Mars' daylength is close to Earth's: 24 hours, 39 minutes and 35 seconds. Need to heat it and pressurize it.
Light would be much dimmer than on Earth - like 42% as bright, give or take depending on latitude.
Considering that Mars' near-vacuum is mostly CO2, we could enrich the greenhouse's air with extra CO2.

The greenhouse would have to provide warmth, water, oxygen and soil. Maybe supplementary light.

Except for the gravity (38% of Earth's) , if the greenhouse mimicked Earth closely enough, it might be able to accommodate almost any Earth plants. (Since Lunar gravity is only 17% of earth, any plants adapted to Lunar gravity ought to consider Mars "heavy".)

The issue might come down to how "expensive" it was in terms of power and consumables hauled from Earth or asteroids to make a greenhouse THAT Earth-like.

We might start looking for (or designing) plants able to grow with LESS light, gravity, water, heat and air pressure. The easier it is to make the greenhouse "tolerable enough" for the plants, the larger it can be with limited resources, and the more people it could support with oxygen and food.

I guess I would start by looking at food crops that have adapted to very cold, arid mountain tops with huge daily temperature extremes (if there are any such crops). Then I would start breeding them and engineering their genes. Ideally, we would start that breeding project right now or sooner in order to be ready by the time space travel is 1,000 times cheaper.

But I wonder if we COULD seed Mars with lichens as part of a terraforming attempt (turn CO2 into oxygen and organic matter)? Assuming we were not concerned about destroying the current ecosystem and any life forms that might be lurking. And assuming that sources of water could be found. And that politicians didn't divert the funding to oil company subsidies.

One science fiction novel presumed some cheap form of space travel (hydrogen fusion powered mass drivers?) but then complained there was nowhere to GO TO (where you could live outside an insulated tin can).

So they sent fleets of ships out to the Oort Cloud, to nudge the orbits of many comets, so they would arch back into the main Solar System and crash on Mars! This warmed the planet and released mega tons of water. I think it would also plow and level the surface like a giant roto-tiller!

The idea was to terraform Mars for some decades or centuries, then move people in and continue terraforming.

I would bet that we would have thriving colonies on Luna and asteroids, and orbiting habitats, decades before we have anything more than sealed domes on Mars with self-sufficient, closed, artificial ecosystems.

Philipwonel said: when are you going to Mars ???

That still cracks me up

They say Mars is the best candidate to terraform, Mars has 1% atmosphere. The planet would need warming up much like what we are doing on earth with global warming, green house gasses.

I think Mars would have been another earth if things hadn't gone so wrong and the same fate could have easily happened to earth. Both planets are in the habitable zone after all.

WillC said:What is the point? There is no life on Mars of any kind except when humans set foot there and walk around in their space suits.

It would be so amazing to terraform Mars starting with a giant greenhouse.

Current research is considering the possibility of using large lava tubes as living space (and probably greenhouses). Shelter from stray debris strikes and poor weather, insulation... They have proven water is obtainable on the planet's surface. Soil is easy to manufacture with a few basic starting pieces and patience. The biggest issue would be light. Solar radiation is less than half of Earth, an efficient power system to run lights and heat would be essential.

You can't put the rest of the atmosphere back on Mars with terraforming, without constant replenishment (think plate tectonics) it would just drift away again.

Just think of all the round trips that you would need to make in order to build any kind of structures on Mars that would be large enough and viable enough in order to attempt to grow anything.
Do you realize the amount of cabbage needed to finance such a project. And I am not speaking about edible cabbage.

They are kind of slowly working towards such an idea with reusable rockets and such but you won't see an agricultural sustaining colony any time soon.
But Amberleaf, I have a question for you. You state that Mars has a 1% atmosphere. 1% of what? How is a 1% atmosphere going to keep anything from drifting off into space? You can't simply pollute a planet like Mars by simply heating it up. There is no atmosphere to hold the heat there. That is why it gets so cold there. There is no atmosphere there either to keep it from heating up during the Mars daytime either.

Although this whole idea makes me think of those closed dome like structures that were erected in our own desert Southwest in an attempt to survive in a harsh environment. Not only survive but be self efficient.

sumire said:Current research is considering the possibility of using large lava tubes as living space (and probably greenhouses). Shelter from stray debris strikes and poor weather, insulation... They have proven water is obtainable on the planet's surface. Soil is easy to manufacture with a few basic starting pieces and patience. The biggest issue would be light. Solar radiation is less than half of Earth, an efficient power system to run lights and heat would be essential.

You can't put the rest of the atmosphere back on Mars with terraforming, without constant replenishment (think plate tectonics) it would just drift away again.

I thought the lighting would be ok on Mars if its in the habitable zone but I guess not and coming to think about it, if the light is poor then it all makes sense why Mars ended up the way it did.

I had read somewhere that Scientists had discovered evidence of possible plant life which may have existed on Mars along with vast oceans of water millions of years ago.

I just had to look it up. The atmospheric pressure on Mars is less than 1% of Earth.
Mars does have an atmosphere consisting mostly of Carbon dioxide 96%, Nitrogen I think and Argon. But it has been leaking these gases or losing the atmosphere there for years and years and years.
So I was incorrect in saying that there was no atmosphere but just one that isn't too conducive to life as we know it. 96% Carbon dioxide does not sound too appealing.

Still am curious as to where the funding is going to come from?

BigBill said:I just had to look it up. The atmospheric pressure on Mars is less than 1% of Earth.
Mars does have an atmosphere consisting mostly of Carbon dioxide 96%, Nitrogen I think and Argon. But it has been leaking these gases or losing the atmosphere there for years and years and years.
So I was incorrect in saying that there was no atmosphere but just one that isn't too conducive to life as we know it. 96% Carbon dioxide does not sound too appealing.

Still am curious as to where the funding is going to come from?

As technology improves, it maybe possible to do it on the cheap in about 500 years time.

I think it is fun to hypothesize, to say "what if". Trying to solve the problems of a colony on Mars is a fun brainstorming exercise. Because we are working on brainpower, for fun, funding isn't an issue. And many cool discoveries and inventions have come from "what if".

The atmosphere on Mars is an interesting thing because it relates back to the basic question of "why does Earth have an atmosphere?". The atmosphere on Earth constantly drifts off into space, but not as fast as Mars because there is more gravity. And the atmosphere of Earth is constantly replenished by a complex cycle of subduction zones, volcanoes, and life itself. Mars wasn't dense enough, and didn't have the right materials to begin plate tectonics.

As a result, life may or may not, (evidence is growing but certainly not absolute yet) have formed in the beginning but did not get far before the planet began to run out of gasses as it cooled. (It even took Earth quite a while to get from single cell to multicelluar organisms.) CO2 is left because it is common, and weighs more than O2.

BigBill said: Still am curious as to where the funding is going to come from?

Dreaming is free and a vivid imagination is good for your health. It keeps you off the streets too.

I'm not sure I want to live in a lava tube though. We will have to put foam on all the walls (turquoise foam ) or pack a lot of bandaids. And can we grow more than just potatoes?

Mars' molten core has cooled , no molten core , no magnetic field to protect it from solar winds and cosmic rays. Solar winds strips away Mars' atmosphere. So without a molten core to produce a magnetic field around the planet there is definitely no terra-forming a new atmosphere on the surface. Tunnels would be the best bet to protect any people from cosmic rays which can damage our and any plants dna.

Who is this important to? How about talking about our gardens today and what we can do better than even talking about Mars. I don't get why this is an important discussion on Garden.Org. Just my thought.