Holidays to the citrus orchard - small trees but fruit very abundant

Last week I was with family vacation to the highlands and there were lots of garden gardens, and we stopped by the orange cottage on the side of the road, very visible orange is very fertile, has lots of fruit despite the short tree, the fruit is very sweet and big, I really like this orange and this tree is very interesting because it is carved small but the fruit produced is great.

very much fruit on this lemon tree, somehow how to make it fertile like this, but in my opinion the weather and soil fertility factors that affect