The tree from which the edible olives originated over the centuries is the subspecies Olea europaea subsp. sylvestris. In East Africa there is another subspecies, Olea europaea subsp. cuspidata, with small olives that are barely edible. In the highlands of Ethiopia; This African wild olive often occurs in church forests, small remnants of natural forest in an otherwise often treeless landscape. Today there are more than 80 varieties of olive trees by interbreeding. The tree initially grows relatively slowly, has a thick trunk and long roots. Due to the growth of the roots, a minimum distance between the trees should be maintained when planting. Only after 5 years does the tree begin to bear fruit. Olive trees can live for many hundreds of years. Old olive trees are particularly valuable. In the Netherlands and Belgium; olives are sometimes grown as a container plant. The older plants can be planted in the ground all year round in these countries. They recover quickly after light frost.