Life

The science behind why stroking your seedlings actually works. If you’re worried about your seedlings getting long and leggy, try a bit of home thigmomorphogenesis, advises James Wong

By James Wong

30 December 2025

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If your windowsills are anything like mine, they are filling up with the first batches of seed sowings for the year ahead. The challenge is that seedlings raised in the cosseted environment of the great indoors are notoriously prone to growing long and leggy, often collapsing just a few weeks after sprouting. But could a colourful old-school technique help keep our gardening hopes for 2026 alive and well? Here’s the science behind why stroking your plants isn’t quite as mad as it sounds.

Plant propagation is often a balancing act. Starting tender seedlings under glass, away from temperature extremes, harsh wind and the constant threat of pests and diseases, greatly boosts their early survival. Yet this lack of environmental stress can have unintended consequences. Etiolation – where plants grow tall but fragile – is a common issue for indoor plants, including those in commercial nurseries. Once outdoors, these specimens are far more likely to physically collapse. With billions of dollars at stake worldwide, it’s no surprise that commercial growers for effective, scalable solutions.