Always choose seeds from the largest pumpkin to plant. These seeds will have the genetics to grow big and if everything else is done correctly in the growing process, you can be very much assured to produce a big pumpkin. In my very first season I planted seeds from a tiny 32kg pumpkin. I managed to grow a 84kg pumpkin from those seeds in that same season. If I can do that in my first season, imagine what you can do with seeds from a 150kg in your first season.
The best way to plant your seeds is flat on its side about 2-3cm deep. The reason why we plant seeds like that is to let excessive water drain quickly away from the seeds before they rot. Prior to planting soak the seeds in warm water for about 3 hours. Do not use hot water. Plant 3 or 4 seeds in each hole you prepared in your patch. When the plants has grown 3 to 5 leaves, keep the strongest plant in each hole and discard the rest.
Plant your seeds early in the season after the last frost and when the days become warmer. If you expect a late frost, cover your plants during the night with plastic or any type of material that will protect your plants from the cold.
You can also start seeds indoors in pots with a good growing medium. Transplant seedlings when 3 true leaves has grown. Be careful as the plants are brittle and can easily be damaged.
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