After broadcasting the ancient times live, I handed the system over to the state.

So... you can grow things without soil?

Even the old farm tools, like the iron oxen, had traceable origins, and people roughly understood their purpose. It's just that later generations changed the shell and used a different method to drive the iron oxen.

But it hasn't reached the point of being incomprehensible.

The hydroponics technology they are using now has really surprised them.

Just like people need to eat and drink, but you can't just drink water without eating, plants can also just drink water without eating.

If this were really possible, how much land would be saved!

They can grow things as long as they dig a pond or put a jar in their home!

Soon, the sky shattered their hopes.

"Hydroculture is a soilless cultivation method where the plant's roots come into direct contact with the nutrient solution below. Of course, it is also necessary to ensure the normal growth and cycle of the plant."

"The nutrient solution used in hydroponics is a new type of plant nutrient solution synthesized using environmental and ecological symbiosis technology, mycorrhizal symbiosis principle, and many other processes."

"This nutrient solution can replace the water and fertilizer in the soil, and hydroponics can also simulate the heat, air and other factors needed for plant growth, thus providing the best environment for plant growth."

"There are relatively few pests and diseases, and management is relatively simple, but the requirements for nutrient solution preparation are very strict. Once there is a problem with the nutrient solution, the plant may suffer from oxygen deficiency, fungal infection, root rot, and so on."

The people under the sky were also suddenly pulled from their beautiful daydreams.

Nutrient solutions, principles, and technologies are all things that only future generations can master. They haven't even finished studying the land beneath their feet, so how could they have the time and energy to research hydroponics?

There are also people who are interested in these things and study them, but that's another matter.

"It's a pity..." Liu Che shook his head slightly.

Liu Qi said, "If hydroponics were really that good, later generations wouldn't have spent so much effort continuing to study soil."

Liu Che opened his rather large eyes and said, "Making these things might be very costly, so we'll just supply them exclusively to those with wealthy families."

Liu Qi gently tapped his head.

After a moment's thought, Liu Che immediately changed his mind, "It should be sold in those stores, it's just that it's quite expensive, but everyone can afford it."

Liu Qi nodded, somewhat relieved. "As we can see from the sky, the yield of hydroponics is not much compared to the whole of China, but it is not little either. If there wasn't a certain yield, Miss Zhu wouldn't have brought it up and acted as if it were commonplace."

As Zhu Qinggu began to describe another type of rock wool cultivation method on the sky, little Liu Che immediately looked up at the sky with great interest and asked, "Father, what is rock wool?"

Liu Qi shook his head as well, "Why don't you ask Miss Zhu yourself later?"

"Perhaps Miss Zhu will say it herself later?" Liu Che smiled shrewdly.

……

Zhu Qinggu mentioned rockwool culture, which is a very interesting soilless cultivation method. She was seeing it for the first time when she was collecting information, as she had heard more about hydroponics before.

Hydroponically grown lettuce is also frequently reported on television news.

There are occasional reports of artificial meat.

"...Rock wool cultivation is actually planting crops into pre-made rock wool. Everyone must be very curious about what rock wool is. In fact, the raw material of rock wool is stone."

The people under the sky were completely shocked!

"Huh? A stone?!"

"Can flowers really grow inside rocks?"

"Now, in later generations, flowers have truly grown inside stones!"

Hydroponics was one of the previous soilless cultivation methods, which makes sense when you think about it. Which plants don't need water? You can grow vegetables in water too. Just add some nutrient solution, and it's like people drinking porridge or soup—they can survive!

Are stones now being used to grow vegetables?

Ying Zheng was also greatly shocked. Now that it was mentioned, he also thought of the so-called "rock" in front of "rock wool". Could things really be grown on rocks?

"You can grow things on rocks?" Li Shimin was somewhat surprised, but he quickly came to his senses. "It must be like hydroponics, using a very special method. The rock wool on the canopy is so soft!"

A hand reached out from the sky, picked up the rock wool, and carefully planted it in a flowerpot.

As the hand picked it up, everyone could see that the so-called rock wool was soft.

Is this really rock? Can rock become so soft? And replace soil?

"Rock wool is made from natural rocks, such as basalt or diabase, with the addition of a certain amount of dolomite or limestone. The mixture is then calcined to form magma, and high-pressure gas or centrifugal force is used to turn the rock into a fiber."

"After undergoing a certain curing process, it becomes a piece of rock wool like this."

A video showing the production process of rock wool was gradually displayed on the screen, and Zhu Qinggu gave a brief explanation.

Then everyone understood.

The iron ore smelters looked at the blast furnaces in the sky with great interest.

They were also very interested in the process of rocks gradually turning into flowing magma.

Currently, they can only burn the iron, unlike in later generations where pressure can be applied. If pressure could be applied, would the iron produced be harder?

Everything about the future is wonderful, except that the future is too far away. They can't touch it or reach it, yet it still makes them drool with envy! Sigh!

……

"Rock wool has good air permeability and water retention. After high-temperature refining, it is sterile and pollution-free, making it the main soilless cultivation substrate in Europe. After the nutrient solution is prepared, drip irrigation is generally used to provide the nutrients needed for plant growth."

“After planting is finished, rock wool can be recycled, then sterilized, crushed, and remade.”

Recycling? That would mean starting all over again, which would be quite costly. Jia Sixie shook his head slightly. "If that's the case, it's not as good as using land. These hydroponic cultivation methods are forward-thinking, but they also have many drawbacks."

Later, Zhu Qinggu also talked about sand culture, which is actually quite similar, except that rock wool is replaced with sand, and it also requires nutrient solution.

However, sand cultivation still has some significance for some relatively dry areas with soil that is close to sand!

After Zhu Qinggu finished explaining these things, she glanced at the clock hanging above the blackboard, and realized that it was almost time to go.

"These three live broadcasts were all about planting. Actually, I'm a complete novice in this field, so I'm just showing off my limited skills in front of so many people. Thank you all for listening."

(Jia Sixie of the Northern Wei Dynasty: Miss Zhu spoke very well, which was very helpful to me. I also learned a lot about the direction of agricultural tool improvement in later dynasties. This is a very good thing. What Miss Zhu did is beneficial to all people!)

(Xu Guangqi, Ming Dynasty: Having witnessed many planting methods in later generations, I have also benefited greatly and have many thoughts to share.)