You need a pollinator to make the nuts curdle. Once you've decided what your main variety of hazelnuts is for production, it's time to choose your pollinators. Since not all hazelnut varieties are cross-pollinated, compatibility is essential. Filbert trees need a pollinator to produce nuts.
All Filbert varieties are not cross-pollinated. Rebecca McCluskey and others have done a lot of research at Oregon State University on pollination. There are a number of problems that need to be solved in order to match the pollination of hazelnuts well. The time of pollen release to coincide with the time of flowering is vital.
The compatibility of alleles between varieties is another very important aspect of pollination. Hazelnuts are monoecious, meaning they have separate male and female flowers on the same tree. Male and female flowers can bloom at different times. Hazelnuts are self-incompatible, meaning that a tree cannot produce nuts with its own pollen.
In addition, certain combinations of varieties are incompatible with each other. In other words, pollen in some varieties does not produce nuts in other varieties. Most plant flowers have an ovary containing ovules with eggs prepared for fertilization, but hazelnut flowers have several pairs of long styles with stigmatic surfaces receptive to receiving pollen and a small portion of tissue at their base called an ovarian meristem. This 4 to 5 month gap between pollination and fertilization is one of the unusual features of the floral biology of hazelnuts.
We've grown and grown your Theta and Jefferson Filbert hazelnuts for the best results, and you get the rewards effortlessly in your own backyard. Because hazelnuts have two sets of chromosomes, they have two alleles for this gene, one on each of the two chromosomes. However, hazel flowers have several pairs of long styles with stigmatic, pollen-receptive surfaces, and a small portion of tissue (0.25 mm or less) at the base called the ovarian meristem. Hazel trees are wind-pollinated and there must be a compatible pollinating variety for effective pollination.
Although hazelnuts are monoecious (they have male and female flowers on the same tree), they are incompatible with each other, meaning that a tree cannot produce nuts with its own pollen. If an allele expressed in pollen matches one of the alleles of the female flower, the crossing is incompatible. However, adding an additional pack of hazelnut pollinators will dramatically increase the size of your crop. This publication provides a glossary of botanical terms related to hazelnut pollination and describes the process of flower and nut development, pollination, and related issues.
Usually, in hazelnut orchards, three pollinating varieties (those that pollinate at the beginning, middle and end of the season) are placed throughout the orchard, not in solid rows. In addition, some varieties are incompatible with each other, making it even more difficult for hazelnut trees to pollinate. The maximum pollination of hazelnuts occurs from January to February, depending on weather conditions. The Theta Filbert hazelnut and the Jefferson Filbert hazelnut are resilient trees that can be planted all year round, although the best time is fall or spring, so that the tree can take root in the ground before extreme temperatures arrive.