Vegetable Vampires 3: Hay rattle

Hay rattle Rhinanthus minor is the quintessential hay meadow wild flower that’s not only decorative but also popular with the bumblebees. It isn’t easy for an annual plant like this to compete with all the other plant species in a meadow but like other hemiparasitic flowering plants its solution to the problem is to dispense with an extensive root system of its own and, instead, plug itself directly into the roots of the surrounding grasses. This has a double benefit, providing it with water and mineral nutrients and suppressing the grown of tall host grasses around it.

In recent years conservation biologists have exploited hay rattle’s grass-suppressing properties in attempts to improve species diversity of degraded grasslands. It’s an easy plant to introduce if you want to turn your garden lawn into a miniature ‘hay meadow’, provided that you make sure that you rake the hay rattle seeds into the soil around the base of the grasses in autumn. It needs prolonged winter chill to break the dormancy of the seeds that tend to germinate in early April. Once the plant has flowered and set seed once it often tends to form a self-sustaining population.

Hay rattle seed capsules are enclosed with leaf bracts and the whole assemblage becomes dry and brittle has the seeds ripen, so the plant rattles in the wind. It’s said that the traditional time to cut a hay meadow was when the yellow rattle begins to rattle.