Here's a link to a post made a few years ago on the same subject.

Also, I think this excerpt from Felix Morrow's 'Revolution and Counter Revolution in Spain' [Source] gives a good description of the economic situation for peasants in Spain:

"The chief industry of Spain, agriculture, accounting for over half the national income, almost two-thirds of exports and most, of the government’s internal revenue, with 70 per cent of the population living on the land, was in desperate straits. The division of the land was the worst in Europe: one-third owned by great landowners, in some cases in estates covering half a province; another third held by more numerous owners but also in large estates; only one-third owned by peasants, and most of this in primitively equipped farms of five hectares [1] or less of extraordinarily dry, poor land, insufficient to support their families, and necessitating day labour on the big estates to eke out an existence. Thus, most of the five million peasant families were dependent on sharecropping or employment on the big estates.

Spanish agriculture was conducted by primitive methods. Its yield per hectare was the lowest in Europe. Increased productivity required capital investment in machinery and fertilizers, employment of technicians, re-training of the peasants. From the landowners’ standpoint it was cheaper to continue primitive methods at the expense of the peasantry. The one recent period of good prices for produce, the war years, 1914-1918, which gave Spanish agriculture a temporary opportunity to profiteer in the word market, instead of being used to improve the land, was capitalized into cash via mortgages obtained by the landowners. Driven out of the world market after the war, Spanish agriculture collapsed. The general agricultural crisis, first preceding and then part of the world crisis, aggravated by the tariff barriers raised against Spanish agriculture by England and France, led to widespread unemployment and starvation."

Even as early as the mid-19th century peasant risings were occurring in Spain. The peasants, who participated in small-scale and semi-isolated labor, were more in agreement with anarchist ideology that favored decentralized systems of organizing and exchange. Also, prior to the Russian Revolution most Marxists had believed the character of successful proletarian revolution would have to take place in an industrialized country, which Spain was not.