Giant pumpkins

 List of most popular giant pumpkin types:

Atlantic Giant Pumpkin (or Giant Pumpkin, or Cucurbita Maxima)

It can weigh from around 150 pounds to over one ton!
It has ribbed and often crumpled thick skin. Colors vary from light pink to bright orange. It doesn't taste great, but it's still edible. Available in the Fall. You can buy seeds
at Harris Seeds.

Big Moon Pumpkin

Photo: Pixabay

It can grow up to 250 lbs. It has slightly rough skin with well-pronounced ribs. It's bright orange and has brown seeds. Perfect for decoration purposes and county fair contests. Harvested in the Fall.
You can buy seeds at Reimer Seeds website.

Big Max Squash

Photos: Rareseeds

They grow big (around 100 pounds), hence the name. They are often bright orange, somewhat flattened. Their skin is rough, medium to deeply ribbed. They have yellow-orange flesh suitable for canning & pie filling. The biggest from the bunch may be quite tasteless, though. They're available in Autumn.
You can buy seeds at Rareseeds website.

Mammoth Gold Pumpkin

Averaging from 40 to 100 pounds. Perfect for carving purposes. It's usually round (sometimes more oblong) with smooth orange skin. Ribbing is often less pronounced, sometimes almost invisible. The flesh can be used for pies.

You can buy it in the Fall.

Seeds available on Amazon.

Full Moon Pumpkin

Photo: Pixabay

Medium to giant (up to 90 lbs!). They have white ribbed skin and thick orange flesh. Suitable for making pies, carving, and decorative displays. 
Available in the Fall.
Seeds to buy on Amazon.

Giant Show King

Photo: Jannine Cabossel, giantveggiegardener.com

This giant squash was developed by Howard Dill.
Because of its size, it's heavily flattened. It has a distinctive green tint, deep ribs and it's an ideal contender for pumpkin size contests.
Available in the Fall.
You can buy seeds at Rareseeds.

'Prizewinner' Pumpkins

Photo: Pixabay

Very popular hybrid pumpkins. As the name suggests, they can help you win pumpkin contests or make an impression on the county fair. They grow very large (between 100 to 300 pounds). They are round with orange or bright-orange glossy skin. Ribbing is moderate.
Available in the Fall.
Seeds to buy at Harriss Seeds website.

Learn more about different pumpkin types: