Key difference: Agriculture is the practice of farming and cultivation, in order to produce food and food products. Horticulture is the act of cultivating a garden for fruits or vegetables, and also maintaining it.

Cultivation is essential to the survival of human beings. We have depended on cultivation for food and livelihood since Stone Age. Agriculture is a type of cultivation that is used to produce food and the products associated with it. Agriculture comprises various activities in its ambit, such as farming, irrigation, cattle farming, sustainable agriculture, animal husbandry, etc. Major economies in the world today have agriculture as one of their pillars of financial solidarity. No business or industry can do away without agriculture, because it provisions the basic necessities of raw materials such as cotton, sugarcane, paper pulp, vegetables, manure, etc. In many countries, agriculture is still pursued as the main occupation by citizens. 

Horticulture is a form of agriculture where cultivation is carried out, albeit on a smaller scale than agriculture. Agriculture involves cultivating on a large scale basis. In fact, as part of agriculture, acres of land are cultivated simultaneously for an optimal level of output. Horticulture too is essentially cultivation, but not of the same degree as agriculture. Horticulture is more inclined towards the domestic aspect of cultivation. An activity like growing plants, vegetables, fruits, etc. in a domestic environment is horticulture. Horticulture may also entail gardening, growing a nursery of plants, growing roots and shoots, etc. Since horticulture is practiced on a small scale, it is comparably less expensive than agriculture.

Comparison between Agriculture and Horticulture:

Image Courtesy: entrance-exam.net, uga.edu