"For the L-rd, your G-d, brings you to a good land a land of wheat and barley, of grape and fig and pomegranate; a land of oil-rich olive and sweet date."
- Devarim 8:7-8
This is how the Torah introduces the seven species of grain and fruit with which Eretz Yisrael is blessed.
These species are mentioned in a number of places throughout Tanach. In many cases there is a comparison between them and our people to whom G-d gave this Land.
Our Sages (Mesechta Succah 5b) even saw in these seven species hints to the various measurements of substance and time, that play a crucial role in halachic matters.
We pay special tribute to G-d after consuming any of these species by making a special blessing, different from the one we make after all other food and drink. Whether it is the birkat hamazon (grace after meals) we say after eating bread made from wheat or barley and their three sub-species, or the condensed version (meain shalosh) said after partaking of cake, wine or the rest of the species, we offer thanks to G-d not only for the food but also for the Land with which it is identified.
Regardless of whether these species grow in Eretz Yisrael or elsewhere, this special blessing is made simply because a species which is described in the Torah as one of the blessings of Eretz Yisrael sets it apart from everything else just as Torah sets the Land and the people apart from the rest of the world.
This is the ultimate expression of our peoples love of the Land.