Sorry for the delay.

Here is a pic of one of the plants. IT just looks kind of thin for the variety that it is.

Here is another. THere were two potential pumpkins on this vine but both turned yellow and fell off. This leads me to believe that the vine is too wimpy to carry a pumpkin.

Thoughts?

They do look wimpy. If they're getting enough sun and water that leaves the soil medium as the likely culprit. Like weirdtrev, I'm suspicious of the quality of your "cow manure". Alot of waste sawdust and wood chips are marketed as soil amendments by mixing and handful of manure into each bag. The wood chips on your soil surface look suspect in this regard. I think you are a victim of cheap soil amendments. That's my 2 cents. Adding liquid fertilizers at this stage of the game I think is of little use, but why not try. Next year try some high quality composts or manures or other organic fertlizers. It takes some research to find out what these are.