Cross-pollination by a genetically different second tree
Although the flowers of the olive tree are hermaphroditic, that is, they are duplex flowers, pollination works best through a second or more olive trees. The reason for this lies in the necessary genetic diversity, because trees with different genetic makeup fertilize better than trees with the same DNA. Self-fertilization is possible under certain circumstances (e.g. with the help of a brush), but it does not bring the desired yield by any means. Incidentally, this also applies to olive trees with the same DNA as are grown by propagating with cuttings - these trees fertilize each other only moderately or not at all.
also read
- Tradition from Andalusia: Olives of the "Hojiblanca" variety
- Olives need sun - in every season
- Are olives hardy?
Pollination in olive trees
Olive trees are rarely fertilized by insects, but rather by wind pollination. The wind transfers the male pollen to the female inflorescence of the other tree. However, since olive trees in our latitudes should better be kept on the balcony or terrace for climatic reasons, wind pollination is difficult to enforce. However, you can help by hand: With the help of a brush, you can transfer the pollen from one tree to the other. You can also shake the trees a little to mimic wind pollination. Olive trees usually bloom between April and June, and later in cooler temperatures.
Self-pollinated varieties
A few varieties are able to self-fertilize. But even with these, self-fertilization only brings a very low yield, cross-pollination remains successful and also more productive. However, if you don't have the space for several trees, but still want to harvest your own olives, you can switch to these varieties:
- Leccino
- Frantoio
- Cailletier
- Aglandou
For a higher harvest, however, at least a second olive tree in the immediate vicinity of the first would be advisable.
Tips & Tricks
Depending on the variety, olives have white to yellow-green flowers, which, however, only appear when overwintered. In order to stimulate an olive tree to bloom, it should overwinter in a light spot at around 8 to 10 ° C. It may not be fertilized or watered very little during this rest period.
