Question: Which species of pollinator visits your plants the most and do specific species like specific types of plants?

John Paterson answered on 13 Jun 2019:

Good question. I use radishes, which are what we would call ‘generalist’ flowers. This means they can be visited by any kind of pollinator so my plants are pollinated by honey bees, bumblebees and hoverflies. Which species visits them the most really depends on the time of year – earlier this year they were getting visited by tree bumblebees a lot, now they’re getting visited more by buff-tailed bumblebees. Later in the summer I expect them to be visited by hoverflies more, mainly a species whose latin name is Helophilus (meaning ‘sun-loving’, because they like warmer weather).

But some species of plant are very specific with which pollinators they attract. Some only try to attract flies, some bees, some even bats or birds. Some are pollinated only by a single species of pollinator – many orchids are like this – and that pollinator can often only feed on that flower. This means they have evolved together and is an example of what we call ‘co-evolution’, meaning the evolution of each species has depended on the other one.

A famous example of this is a big moth called Darwin’s hawkmoth. It feeds off and pollinates an orchid called star-of-Bethlemhem. The flower is almost 12-inches long and only this moth, which has a long mouth like a straw which is also 12-inches long, can feed from it and pollinate it.