That is some nineteen fifties agricultural policy right there my friend.

Intensive agriculture has higher output per input than extensive agriculture. The only reason extensive agriculture is preferred to intensive agriculture is because historically land is relatively while cheap, while capital is relatively expensive, however, in Korea the relationship is clearly inverse, capital is inexpensive, land is expensive.

Extensive agriculture has been a failure, in some places more so than others, however, the growth of extensive agriculture over the last century has been dependent on the opening up of marginal agricultural land to farmers, as well as non-marginal virgin land, bringing with it ecological collapse through rising water tables, salinity, erosion, deforestation, decreasing trans-evaporation, increased evaporation, loss of top soil, and falling precipitation etc.

Intensive agriculture has its issues as well obviously, but for many countries, especially in East Asia where the process of urbanization over the last past half century and a bit has occurred primarily in their most fertile regions, land use conflicts have become the single greatest political issue these countries face.

Urban farming sounds strange, silly, futuristic, but when you have no more virgin land to bring under agricultural production, or that which you have left is more productive left as nature reserves than being farmed, then its the only solution.

As for putting seeds in the ground, well, first you need fencing to keep livestock, vehicles and game out, access roads, possibly dams, irrigation channels, pumping stations, wind mills, sheds, silos etc. Then you need farming equipment, so you will need your tractor or tractors, the same tractor might suffice for both plowing, sowing, spraying, and harvesting, but you will need the different components for it, or alternatively just hire all of them.

Then again putting seeds in the ground makes sense if you're growing cereals but not much sense if you're growing strawberries or lettuce, which is much more likely the case for our Korean urban farmers. Even if you where growing cereals the reality is that by keeping the building tightly climate controlled you could probably grow the stalks closer together since you could put the temperature at the right level to prevent the growth of mould, and through proper irrigation and fertilisation you could grow cereals with larger heads than conventional extensive farming since there will be no wind inside your farm towers to knock them over in addition to the better growing conditions.

Anyway, I'm rambling now. It makes sense in Korea.