Before the agricultural revolution there was the open field system was used. There were strips of land which were shared between farmers meaning that no one had any privacy on their farm.
There were many disadvantages of the open field. Disease could spread quickly and easily among animals from different strips. Although the strips were shared one farmer did not always have all his strips next to each other so a lot of time could be wasted travelling from one strip to another. Also there were gape between strips which wasted land. All the farmers had to agree any major change so no farmer was independent.
There were of course advantages to the open field system as it allowed farmers to share land, tools and other equipment.
Before the revolution there wasn't very good transport so goods were much harder to transport to a market.
The crop rotation was very wasteful because every three years a filed went to fallow and so one filed was totally wasted for a whole year.
There weren't very good tools around so the crops were much harder to grow.
Fertilisers were not as good so there would be fewer crops produced in a year.
All of these points made the overall productivity much worse but at this time there was not as great a population to feed so everyone was still being fed.
The main cause of the agricultural revolution was the demand of food because of population growth (it doubled between 1760 and 1820). Because of this prices went up quickly and a farmer could have sold something for twice as much in 1790's than in the 1780's.
The war with France interrupted overseas supplies with Europe so all food had to be produced in England itself. This put a...