It might be a deeply uncool thing to admit, but there are few things I enjoy more than trawling academic databases for obscure articles about plant science. Especially when, buried deep in the geekspeak, you discover really useful, evidence-based tips that are easily translatable to gardeners at home. However, at the end of last year, I stumbled upon a study that seemed too weird and too wonderful to be true: how to use an electric toothbrush to improve crop yields. Having tried it myself this summer and seen how surprisingly effective it is, despite how gimmicky it sounds, I thought it was high time I shared it.
Now hear me out – I promise this is not a wind-up. Many plants in the nightshade family, from tomatoes and chillies to peppers and aubergines, rely on what is known as buzz pollination. This is the process by which the rapid ultrasonic vibrations emitted by species, such as bumblebees, releases pollen grains, which are otherwise tightly held in the anthers of flowers. It is a mechanism finely tuned by millions of years of co-evolution.
Having tried this trick this summer and seen how surprisingly effective it was, I thought it was high time I shared it
The problem is that if there are not enough pollinators around, which can often be the case, growers of such crops may experience poor yields. This is particularly likely when growing these plants indoors, such as in a glasshouse or on a windowsill, as the pollinators simply can’t get access. Traditionally, horticulturists have used a tuning fork, which mimics the high-frequency vibrations of the bees, to trick the plant into releasing its pollen.
However, there are a few potential issues with this technique. First, tuning forks come in many frequencies and only a few replicate that of the bees that are effective pollinators of nightshade plants. Second, evidence has shown that the duration of vibration is of key importance, which means constantly striking the fork for each flower. Finally, how many of us have a tuning fork – never mind of the right frequency – hanging about the house? And if you pay out to get one, what on earth are you going to do with it for the rest of the year?
Given these limitations, a team of scientists at the University of Texas Rio Grande Valley decided to run a beautifully simple experiment comparing the efficacy of using an electric toothbrush with that of a tuning fork. They found that removing the brush head and touching the metal nub to the centre of an open flower and letting it vibrate against the bloom for five seconds was enough to trick the plant into self-pollinating.
In my small, backyard trials this year I found as much as a 20% boost in yield for something that took me less than 10 minutes to do. An uptick comparable to adding more fertiliser, water or moving the plants to the sunniest spot in the garden, for really very little time and effort. A pretty neat trick, even if you do look like a bit of a weirdo doing it.
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