I started the giant pumpkins. Here's my process:
1. Choose the seeds. I chose the 2517 Haist, largest pumpkin in the world last year, 3rd largest ever grown. It's a selfed cross, 2005 Haist x self. The 2005 Haist has done well in less than ideal conditions, and I thought it'd do well here in Colorado. I also chose the 2269 Haist as my back up. It's a 2003 Haist x self. The seeds are pale with very little hard coat. They look a lot like the 800 McMullen seed that grew the CO state record. I grew two 800 McMullen seeds two years ago but lost that season to squash bugs and cucumber beetles. I took last year off and let the beetles find a new home. This year, I'll build a better screen house.
2. File the seed edges. I lightly file the edges with a fine grit sandpaper, careful not to damage the point where the radicle grows from. These seeds didn't need much sanding as the coat was so thin already. This practice helps the cotyledons emerge from the seed.
3. Soak the seeds. I soaked them on 4/9 in a weak solution of previously boiled water and humic/fulvic acid for nine hours.
4. Plant and Germinate. I plant the seeds in moistened Promix and Jiffy mix. I mix the Promix with extra mycorrhiza, worm castings, kelp meal and compost and put that in the bottom of the inverted 32oz containers. I top them off with jiffy mix. I germinate the seeds in an old cooler with a heat mat underneath. These seeds took a little longer to germinate than I expected. The 2517 and 2269 were both breaking the soil on 4/14.
5. Transplanting Up. I transplant up into inverted five gallon buckets with the bottoms cut off and the lids on. That helps me keep the plants indoors longer and also helps keep the roots undisturbed at transplanting time. I transplanted on 4/19, a day or two behind my previous years. These plants were a little behind, possibly due to my using a heavier potting mix--I used the same Promix mixture here. The rooting was good, but also not as intense as it was with the 1685 Scherbers or 800 McMullens I grew two years ago. I had also started a 1685 Scherber x Sibb as a second back up this year, but it didn't germinate. It also appears that the 2269 has some malformity. It's cots are oddly shaped, and it's a week or more behind in leaf development. It has developed a malformed first true leaf. I'm letting it grow to see if it will grow out of this, but it's not looking good. The 2517, though a few days behind previous years' plants, looks normal and healthy. If weather permits, I may get it transplanted into the heated hoop house early next week--a week ahead of my previous plantings. It's odd not to have a viable back up plant, but that's the way it went this year. All eggs are in one basket.