Hello!
Yes I've grown pumpkins and I'm growing 2 plants this year. I grow mine in grow-bags, 1 to a bag, to which I've added a shovelful of farm manure. I also feed them every 2 or 3 days with Miracle-Grow.
Now then - the flowers - this is where you have to be like Robert Winston, well you don't have to be but it helps. Pumpkins have male and female flowers. The first flowers you get are likely to be male. They are bright yellow and have a long stamen, inside the petals, covered in pollen. Female flowers are also bright yellow but have a little bulge just below the flower (the future pumpkin) and a more complicated, rounded arrangement inside. (I know, it's getting very biological isn't it? It gets worse.)
Right, now you could leave the pollination to the bees and it might work. On the other hand, it might not, so this is where you come in. Watch your plants carefully and on the day you get both a male and a female flower opening together you need to get out there early (I'd say before 9 a.m.). Pick off a male flower and pull its petals off and you are then left with the pollen covered stamen. You then need to poke this stamen all around and into the stamen of the female flower, transferring the pollen. Once you've done this, with a bit of luck, the tiny embryo pumpkin will have been fertilised and will start to grow.
Best of luck, it's an absorbing hobby.
