There is art which displays different colors of pumpkins, green and white to provide a bit of variety to the vegetables normal style so that it doesn't all have to be a Halloween orange. Posters of a pumpkin patch show off the field with the pumpkins still holding their green vines - some posters as pictures, others as realistically styled still life.
Photographs of pumpkins in different positions - whether they are pictures of jack-o-lanterns in a great and awesome display or photographs of two kittens sitting inside of a large, hollowed out pumpkin - can be framed and placed in any spot of the room where they fit. These pictures and posters aren't just for a kitchen, but might do the right job of adding flavor to a living room at the right time of year or to sit on a wall at any point in time.
It's important to consider the surroundings when placing up photographs of pumpkins - the orange color and simple style of many paintings mean they can fit in many areas, but will clash with bright colors like bright red or blue - but do a good job complimenting other oranges or beige.