Which Plants Are Best for Bees?

Bees rely on pollen from plants and flowers to feed their young. While those species which produce nectar are most desirable to bees, the most important thing for their survival is access to a steady supply of pollen throughout the year. As a result, bees may turn to unlikely alternatives to sustain themselves and their hive when pollen is scarce.

One such plant which has proven itself popular with bees in Colorado, America is hemp. Most famous for being a variety of the Cannabis sativa plant which is now cultivated for the production of marijuana in the States, hemp has not traditionally been associated with bees, but a recent study found that it may provide an important food source for the struggling species in times of need.

Beleaguered bees

Bee populations all over the globe have been struggling in recent years due to a variety of different factors. An increase in industrial agriculture has led to a loss of habitat, while the widespread use of neonicotinoids as pesticides has had a significant impact on their numbers. Fortunately the UK government moved to ban such chemicals earlier this year.

Meanwhile, climate change has caused instability in seasonal rhythms, affecting how flowers bloom and directly impacting the primary food source for bees. This means that in spring and autumn, bees can suffer from a shortage of sustenance and may look to unlikely sources to supplement their nutritional intake.

Hemp to the rescue

Hemp does not produce nectar, and therefore normally relies on wind alone to serve its pollination needs. However, Colorado State University etymology student Colton O’Brien noticed an interesting phenomenon last year when monitoring hemp crops as part of his studies. Since many of the bees’ preferred crops had already finished their flowering cycle, the later-blooming hemp provided a valuable source of nutrition during autumn months.

In total, O’Brien observed 23 species of bee visiting the hemp fields, 80% of which belonged to four groups. O’Brien believes that this unanticipated environmental benefit should be emphasised when planting hemp crops in the future.

Pest control

In particular, O’Brien highlighted the challenges facing pesticide analysis and monitoring. Given that hemp growing on a commercial scale is still a relatively new endeavour, having only becoming legal with the passing of the 2014 US Farm Bill and set to increase under the 2018 Hemp Farming Act, much remains unknown about pesticides with regards to hemp produce.

Exactly which insects will pose the greatest threat to the longevity of the crops is still a mystery, as well as which pesticides should be used to best deter them. O’Brien is hopeful that farmers will be mindful of bees when spraying pesticides in the future, as they may well come to increasingly rely on the food source as climate change progresses.