The pumpkin plant produces easily up to 8 pumpkins. If you leave all 8 pumpkins to grow big, the plant can not produce enough food for all 8 pumpkins to become the monsters you are seeking. It is obviously the best to have only 1 pumpkin per plant. When the pumpkins reaches the size of a soccer ball, it's time to make that heartbreaking, but very important, decision on which pumpkins to keep and which to remove from the plant. Choose the pumpkin that's growing fastest. Also look at the shapes. Those that are round usually grows the biggest. If you want to play it safe, keep 2 pumpkins per plant but after 2 months one must be removed.
The position of the pumpkin on the vine is extremely important. The best position is when the stem is at right angles with the vine. If not move the pumpkin till it's in the correct position. This is a delicate process and must be done by moving the pumpkin not more than 4 or 5 mm a day.
Well that's it. This is only a starting point in growing giant pumpkins. I recommend that you gather as much information as possible on the subject. A good place to start is to do a Google Search. I wish you all the best with your venture to become the next world champion.
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