Dear Readers, I was reading a very interesting article in my Royal Horticultural Society magazine this week, about the different amounts of nectar sugar that gardens produce. In a study of 59 urban gardens in Bristol, PhD student and research assistant Nick Tew found that there was a massive difference between the amounts of nectar sugar produced by the different plots, varying from a measly 2 grams in the least productive garden to a whopping 1.7 kg in the most productive. What interests me, though, is that there wasn’t a correlation between the size of the garden and the amount of nectar produced – many of the bigger gardens had large amounts of lawn, which isn’t useful as a nectar source (though longer, more diverse patches of grasses do have other uses).
Stephanie Bird, the RHS Plant Health Scientist, points out that, in comparison with gardens with a large proportion of lawn
“Smaller gardens packed with plants are more beneficial, and if you don’t have a garden, then containers and windowboxes will still make a difference”.Gardens in affluent areas did tend to produce more nectar sugar, and I wondered if this was because people had more money available for plants, and maybe more time to tend them, or to pay other people to look after them. Interestingly, trees, shrubs and climbers provided two-thirds of the nectar sugar, because they tend to pack more flowers into a small patch of ground.
Another thing to consider is the shape of the flowers in the garden. From July to October, apparently 80% of the flower nectar came from plants such as fuchsias and salvias, which are lovely for long-tongued pollinators, but which render the food unavailable to many other insects. The suggestion is to grow lots of single blooms or open flowers at this time of year – I’ve noticed how popular my asters and sedum are with a whole range of pollinators as we head into autumn, so this sounds sensible to me. Incidentally, sedum is no longer sedum, but is now hylotelephium. The new name apparently means ‘woodland distant lover’ – the plant was thought to be able to indicate when one’s affections were returned, though irritatingly I’m not sure how. On the other hand, I also read that ‘telephium’ referred to King Telephus, who suffered a spear wound that wouldn’t heal, and that was treated with this plant.
So, in a way this report is nothing new – I think we’ve been aware for while that the more plants we had in our gardens/containers/ windowboxes the better, especially if coupled with a longer flowering period and a good array of flower types (not including double flowers which are too complicated for the pollinators to access, and which often don’t provide any food value). But what gives me a spur to action is the headline that you don’t need to have a massive garden to make a difference. It’s also a good illustration of the way that having lots of gardens all providing slightly different things at different times is ideal for flying insects, because it means that there’s always something to eat. Urban gardens in particular provide a patchwork of habitats, plants and flowering times in a very small space. This is all very encouraging, and inspires me to up my flowering game even more this year. Let’s see how we get on!
You can read about Nick Tew’s research here.