Almond Pollination

Recommendations

• We recommend a minimum of 8 bumblebee hives per hectare when used as the only managed pollinators. Ideally space the bumblebee hives evenly throughout the crop.

• Bumblebees can be used with honeybees to continue to provide pollination when the weather is poor and honeybees won't pollinate, but keep the bumblebee hives as far away from any honeybee hives as possible and spread them throughout the orchard (not around the edges or all together). Use a minimum of 4 hives per hectare for reasonable coverage.

Longer-term research under Mediterranean conditions as well as work done in Israel has shown that the introduction of commercial bumblebee hives can significantly improve the pollination of almond crops compared with using just honeybees and natural pollinators. The yield increases improved the economic balance for the growers.

Bumblebees are much more active than honeybees during poor weather and will fly at significantly cooler temperatures, making them ideal pollinators for early flowering crops like almond. The large size of a bumblebee assists in its deposition of pollen, and bumblebees have shown high mobility when foraging in orchards, increasing the likelihood of cross-pollination.

The Biology of Almonds

Most varieties of almonds require cross-pollination from a compatible pollenizer variety. Inadequate pollination results in reduced yields.