The first ingredient you'll need is a Jessie's bucket of rain water. This should be as freshly collected as possible.

The pour two compton flasks of bone meal, the plant growth powder, into your cauldron.

Next you'll need a shovel's load of Transylvanian top soil, to add nourishment to the concoction.

Your potion will also need some kind of fertiliser, like fresh camel dung from its bottom pipe.

And to bring your potion to life and give plants the power of spontaneous growth, pour in about a quarter of a Titchmarsh of triffid water.

Then stir your mixture well and collect some of the potion in the drinking device, like a glass, a mug or a glass mug. Drink it and then the next morning you should find that you now have green fingers.

If you want a plant to grow, simply give it a gentle tap. You can even use your green fingers to encourage a seed to instantly grow.

This power will remain with you for about 48 hours, but can be less powerful during periods of intense sunshine and it can be washed away by heavy rain.