Another Pumpkin Question

[KitchenGardener]

What would cause my immature pumpkin to start turning orange? It is a c. pepo, and while it went through a not terrible bout with powdery mildew, I got it under control with milk and Hydrogen peroxide spray. It had set a pumpkin which was growing fine but even for a sugar pie pumpkin, it is quite small. It has now begun to orange. What would cause this? Is this a lack of nutrients? water? I routinely cut back unhealthy leaves (powdery mildew) and feed with kelp/fish emulsion and compost. Any ideas to avoid this from happening again?

TIA!

[KitchenGardener]

Think I found my answer, which is that I may not have been providing them with sufficient water to have them grow as large as they would normally grow...I am now providing more water in the hopes that the next fruits the plants set will grow to a more normal size. If they do not, I have to assume there are deficiencies of nutrients in the soil.