See, I told you that I would bounce back from the failure that was The Penguin...
Using the same basic pattern for increasing the circle I added more stitches until I had the size of circle that I was happy with and then carried on in the round until the pumpkin was as high as I wanted it. Then I started to decrease the stitches, filled the ball with some acrylic stuffing (top tip: do not buy the expensive material which is sold specifically for stuffing but buy a couple of cheap pillows from IKEA instead and take the stuffing out of them. I get a small pillow for 0.80p/$1.00 and the inners are plenty to play around with!).
Once the stuffing and sewing up was done. I took some embroidery floss in a slightly darker colour than my yarn and threaded it through the middle section of the ball. Depending on how many "ridges" you want, you continue to stitch right through the middle section over and over again. The harder your pull your thread through, the more prominent the section will look in the end.
The stem was created by crocheting with some embroidery floss, as I did not have any dark green yarn to play with. Thankfully I had a small hook handy, which worked perfect with the floss.
Once the stem-tube was done, I filled it with some stuffing fastened off and stitched to the top of the pumpkin using invisible thread (LOVE that stuff).
Of course it is still not perfect, but I am quite pleased how this project turned out and I am already looking forward to next year's Halloween, when my wee pumpkin will be on display.