The Sumerians were an agricultural people, and they raised crops in three areas. Inside the city, highly cultivated gardens were kept. The main source of food and surplus came from fields outside of the cities, irrigated by a system of canals from the Tigris and Euphrates rivers. The third agricultural region was the large tracts of land away from water sources. These were used for grazing animals, hunting, and for collecting fuel. The date was an especially important food of the Sumerians, it was highly nutritious, it kept well, and it could be grown in salty or stagnant water. It only needed to be kept wet in order to produce fruit. Other important crops included corn and flax.
The plow was first introduced in Sumer. It was made of stone, and later copper. An innovation the Sumerians also invented was a plow with a seed funnel behind it. The Sumerians used hoes and spades to cultivate fields. These were made out of flint or copper. Sickles were made out of clay which was fired longer than normal. Public institutions such as the city temple and government owned most of the large land tracts and rented out their use and expensive tools like plows and animals to pull them.
The reason so much is known about a people in a time shrouded in obscurity is because of the clay from the rivers. The Sumerians used clay to build their cities and houses. They used it to make bricks which they baked and built the city ziggurats with. Clay was used for tools and for pottery. Most importantly however, clay was used for writing. This was what set the Sumerians