CUCKOO spit is a white frothy liquid secreted by the nymphs of sap-sucking froghoppers, aka spittlebugs.

They do no harm to plants here in the UK and are a sign that all is well in their ecosystem.

Usually cuckoo spit appears on willow, fuchsia, lavender, rosemary roses along with other plants in the spring. This year has had a soggy start so, like the cuckoo it is named after, cuckoo spit is happening now, in late May.

So why do the nymphs live in a blob of foam?

A parasitic wasp, Argogrytes mystaceus, lays its eggs on the nymphs. The foam makes it harder, though not impossible, for the wasp to get a grip on the nymph to deposit an egg.

There are nine species of froghopper found in the UK. The adult froghoppers are small, 5-7mm. They range in colour from browns to black and white and black and red. The nymphs are pale green.

Adults and nymphs feed on plant sap. They have a beak that works like a drill at the front of their heads which they use to access sap.

Froghoppers’ jumping abilities are astounding; reaching up to 70cm, which makes them one of nature’s greatest jumpers in relation to their size.

The G-force generated by their jumps is around 70 gravities. That's 65 times greater than the G-force astronauts are subjected to!