Cold-processed compressed biscuits are a temporary source of vitamin C, which can solve Tang Yue's urgent needs, but after all, it is not a long-term solution, and the truly sustainable source of vitamins must be fresh fruits and vegetables.

Mai Dong patted his chest to Tang Yue, and swore that the tomato seeds on Kunlun Station are definitely excellent varieties, with short growth cycle, strong disease resistance, rich nutrition, sustainable reproduction, and a very high survival rate of seeds.

Tang Yue silently glanced at her chest, skeptical...... I don't know if Mai Dong's conclusive guarantee is as negligible as her bust.

After drinking the extracted vitamin C solution, Tang Yue felt that his physical condition was slightly better, and his whole body was full of strength, he tried to move his hands and feet, and slammed his hand knife on the table with a loud shout...... The next second, he covered his hands and rolled on the ground in pain, "Oh, mom, why did it really hurt me,-".

In fact, Tang Yue also knew that this was mostly a placebo effect, even if enough vitamin C was supplemented, the effect would not be highlighted so quickly, and he had to drink vitamin solution for another week before his physical condition could improve.

Today's breakfast is naturally the biscuits that were spoiled yesterday, after a night of playing, the big lump of earthy yellow paste has dried, formed an irregular lump, and there are still five clear fingerprints on it, Tang Yue frowned, and sat in front of the table for twenty minutes, not knowing how to put his mouth.

"Tang Yue, are you cold?"

"It's cold, it's cold." Tang Yue trembled, "Why don't you hug me?" We can hug each other to keep warm, and it is said that girls' body temperature is higher than that of men. ”

"Then it's better to be cold."

"It's ruthless." Tang Yue pursed his lips and wrapped his clothes tightly.

"Do you want to start growing tomatoes today?" Mai Dong asked, "How about the seeds that were germinated last time?" ”

"They're still there, I've protected them very well, and all the seeds are white." Tang Yue returned to the crew compartment and took out the cassette box from his sleeping bag, which was a small greenhouse, and the ten seeds that had been germinated last time were lying quietly on the gauze in the greenhouse, and Tang Yue protected the seeds on the night when the temperature control system of the OGS cabinet failed.

Tang Yue made a simple improvement to the tape box, installing a small light bulb inside, then connecting the wires and batteries, using the common materials found everywhere in Kunlun Station, the light bulb provides light and temperature for the seeds, and Tang Yue also uses a dropper to add water to the gauze every day to keep it moist.

Tang Yue poured out the seeds in the box, and thanks to his careful care for so many days, the seedlings were still alive.

"Since there's nothing wrong with the seeds, let's look at the fertilizer."

Tang Yue nodded, and brought the jar full of fertilizer to the table, after a long period of fermentation, the poop brothers finally transformed gorgeously, as soon as they opened the lid, a mellow and rich breath of life came to their faces, Tang Yue lost his sense of smell the moment he opened the lid because he was too close.

He was dizzy, stumbled backwards, put on three layers of masks, and put his helmet over his head.

The fertilizer in the jar was brownish-black, Tang Yue found a stick and stirred it vigorously, it was obvious that the fermentation effect was quite good, although on Mars, the microorganisms in the stool were still powerful, Mai Dong glanced at it, and said that it was very much like a jar of sauce...... This girl's bad habit of using food as a metaphor can't be broken.

"Remember to measure the pH of the soil." Mai Dong reminded.

Tang Yue took out a PH test strip and roughly measured the pH value of the soil.

"Hmm...... It's about 7.2, which is neutral. ”

“OK！ This is just the right number for you to plant the seeds, remember to bury the radicle face down in the soil. "But I recommend that you heat up the soil before planting, the most suitable soil temperature for tomato root growth is about 20 degrees Celsius, and raising the temperature can promote the growth of the root system." ”

Tang Yue dragged out the iron frame and electric heater, put the sink, and then poured half of the water into it, and he wanted to heat the fertilizer jar in a water bath.

Tang Yue vaguely remembered that the chemistry teacher in middle school had repeatedly emphasized that the sink could not be heated, and Tang Yue's current operation method seriously violated the laboratory safety rules, but Tang Yue didn't bother to care about any rules and regulations, unless the chemistry teacher and his old man appeared outside the door of Kunlun Station at this moment, no one could stop him from directly baking the glass sink.

Seriously, at this point, Tang Yue has a bit of the courage to play life, and if there is a microwave oven in Kunlun Station, he even wants to try roasting two grapes in the microwave (1).

It is impossible to heat the soil in the jar to exactly 20 degrees Celsius, as it is not possible in terms of the conditions inside the Kunlun station, because the soil is not a good conductor of heat, and you may burn the stool on the outside of the jar, and the stool on the inside is still in the low temperature. So Tang Yue used a short but repeated heating method, staring at the thermometer to let the fertilizer jar heat up slowly and evenly.

When the liquid column of the thermometer stabilized at 30 degrees Celsius, Tang Yue scooped up the fertilizer jar from the water bath, set it aside to dry, and then threw the second fertilizer jar into the sink to heat it.

"It is best to keep the ambient temperature of tomatoes around 25 degrees Celsius when growing, and in addition, pay attention to light, the appropriate light intensity for tomatoes to grow is 30,000 to 50,000 LX."

"Lux?"

"The illuminance unit of light, the illuminance of 1 lumen evenly distributed over an area of one square meter, is one lux." Mai Dong gave the standard answer, "When we are usually outside, the illumination of the sun we see on a sunny day is 50,000 lux. ”

Tang Yue understood, he stared at the fertilizer jar and thermometer heated by the water bath, "In other words, I'd better give tomatoes the light of normal daylight brightness on earth?" ”

"Yes, and you should also pay attention to the time of day, you should give the tomatoes at least eleven hours of light a day so that they can grow faster."

Tang Yue scratched his head, "These things are so delicate, they are even more difficult to serve than a big man like me." ”

"You have to remember that you have in front of you the most complex and fragile and amazing life structures in the world, they are the result of hundreds of millions of years of evolution, and there were plants everywhere on the earth before, so you don't think there is anything unusual about tomatoes." "But on Mars, you look out the window, you look at the endless wasteland, you look at the cold and endless space...... Ninety-nine percent of this world is made up of inorganic matter, don't you think that life is a rare miracle? ”

"I don't just think life is a miracle, I think poop is a miracle now." Tang Yue sat on the chair and looked at the fertilizer jar in the water bath with his eyes stupid, "I used to think that poop was disgusting...... It's unbelievable, what was going on in my head at the time? Why do you hate something so cute? This is a precious source of life. ”

Mai Dong was stunned.

"Seriously, if we can go back to Earth, I'm willing to let me be a manure digger." Tang Yue was serious, waved his fingers, and his tone in reverie showed great envy, "Think about it, inexhaustible stool...... What a wonderful world it was. ”

((1) Author's note: Heating two grapes next to each other in the microwave will cause a large concentration of energy and a sharp increase in temperature, which will produce plasma and cause a fire, which is a very dangerous behavior, do not try!) ）