I’m on my third water butt, but these are serial, not parallel, relationships. I had my first, as a kid, collecting water from my beloved first greenhouse. My second, many, many years later, collected water from our beloved summerhouse, swathed in jasmine and roses, and from whose upper room, we could hear the waves on the beach. My current butt collects rain from our rather grand little shed, which will soon be enveloped in roses etc. etc.
I don’t often look in water butts, like Narcissus in love with his own reflection, but the other day I did. There, in the clear water, the butt itself only a month or two old, were thousands of mosquito larvae flicking about in the shadows.
Being all for wildlife, we do draw the line at mosquitoes, especially as the butt is right next to a seat that catches the last rays of the sun, and is also in front of the open fireplace where we sometimes cook supper.
My first water butt must have had the same problem, for my father bought a goldfish for it, which was soon called Humphrey. Humphrey survived for several years, not, as I recall, getting any bigger on his meagre diet, but at least my father didn’t get mosquito bites whilst harvesting his beans. Eventually, Humphrey came to a nasty end, getting stuck in the outlet of a hastily filled watering can. We tried to blow him back out, but his (or perhaps her) scales stopped this happening. Still, perhaps the fish was lonely and thought the watering can a good way out.
The second butt must have offered mosquitoes a great breeding ground, but I can’t say we ever noticed any problems with it. That garden kept us so dreadfully busy that we were probably always moving too fast to allow a mosquito to settle. Perhaps the drifts of petals fallen from the rose (Gertrude Jekyll’s favourite ‘The Garland’) asphyxiated them.
Perhaps that gave me a clue as to what to do with Water Butt III. Firstly, I tried spraying it with the olive oil sprayer that’s suppose to keep one skinny. It covered with water surface with a nasty looking gunge that certainly scared the larvae down into deep water. Once back on the surface, it seemed to get into their bristles but didn’t stop their air periscopes from getting what they needed. The sprayer went back up to the kitchen. Washing up liquid? That should reduce the surface tension sufficiently to stop the larvaes’ periscopes staying dry, flood them with lemon scented water, and so drown them. Well, I made plenty of bubbles on the surface, but these cleared quickly, and I could see again, the minute opening on the periscopes clicking open as the larvae breathed air. Insecticides? Well the barrel’s water is used in part to water some big pots on the margins of the nearby lily pool, and as that is home to frogs, newts, and much other wildlife (no mosquito larvae though – I checked). Killing off the water butt’s larvae might kill much more that I intended.
A cup of coffee helped. An idea! It seemed brilliant at the time. Cling film. Back to the kitchen. Plenty in stock. After all, it’s opaque to food smells, and so probably oxygen. It’s tough. And it floats on the water surface as if it’s designed to do just that. It even stuck happily to the inside of the water butt, so there were not cracks to the outside world allowing the larvae to breed. And nowhere for a roving female mosquito to lay her eggs. Perfect.
Yesterday morning, no sign of any larvae at the surface beneath the film. Nevertheless, I left it in place just in case larvae can go into some sort of suspended animation. Rain is forecast – it will be interesting (to me, anyway), what happens to the cling film when more water pours into the butt.
If it doesn’t work, there’s only one other possibility. Another Humphrey, or even two. And take a lot more care when filling the watering can.