50% or more of the work for growing a giant pumpkin isn't done during the growing season. It is done in the fall and early spring. It doesn't matter how great your pumpkin seed genetics are if you don't have a great soil to grow it in. I'm starting a new patch for 2009. My good neighbor Chris is allowing me space on his 3 acre property to grow 4 plants next year. A BIG thanks to him for letting me do this. He has gone above and beyond by having his employees use his earth movers to help me move the soil and compost piles.
Soil preparation starts with a soil test. Unless you know what is in your soil you don't know what you need to add. The soil for my new patch was pretty poor. It was compacted, low on NPK, low organic matter and had a high ph of 8.1. To build the soil I added poultry compost, alfalfa meal, bone meal, green sand, humic acid, organic 10-5-5 fertilizer with calcium, tree leaves, elemental sulphur, peat moss and aluminum sulphate. That was all rototilled in deep.
After that I put down a cover crop of annual rye grass and white clover seed. I then spread a 4-4-5 fertilizer with mycorrhizal fungi and sprayed it all down with Neptune's Fish & Seaweed, compost tea, molasses and some fat free milk. The last 5 items were added to help build the microbiology in the soil. The good bacteria and fungi will then start working those soil amendments and turn them into great soil. After that was completed I then ran the sprinklers and covered the main growing areas with 10x25 clear plastic sheets to help build warmth in the soil to get the cover crop going before we get a hard freeze.
In early spring I will do another soil test and will probably add additional composted manure and other amendments as needed. I will also add some worms to the soil as I didn't see any in the dirt today.
As I re-learned today, if you think it will take 3 hours to get your patch prep work done count on it taking 6 hours. Man am I sore and tired tonight.