Ed and Oucho's Excellent Inventions - Series 1 - Gardening Dragon

Ed and Oucho are travelling all over the country making inventions from bits of old rubbish they find in the back of their van. They are trying to build Dolly the Gardening Dragon a dragon that can dig, water, plant seeds and has a hot chocolate tummy. It starts off well, but then Ed and Oucho realise their invention isn't very dragony, can't dig and doesn't have hot chocolate. With the Big Big Cheese on their backs, will their general uselessness and lack of science know-how stop them from building Dolly in time?