Pumpkin

A pumpkin is an uncommon block that appears on grass in a similar manner to mushrooms but does not spread. They can appear in a variety of biomes, usually in groups but occasionally alone.

Pumpkins can currently only be found with a carved face. It was originally stated by Notch that they were to be found and then subsequently carved by crafting. Instead, pumpkins can be crafted into jack 'o' lanterns (see below). Jeb has stated that pumpkins may eventually spawn uncarved.

Pumpkins cannot be placed without a block under them. However, you can place them and remove the block directly beneath and it will remain in place. This reveals that the bottom texture is the same as the top. When placed, pumpkins automatically face the player.

When a pumpkin is pushed by a piston, it breaks. It also cannot be pulled by a sticky piston.

Uses
Harvested pumpkins can be equipped as a helmet without any actual armor value. It is unique in that it limits the player's view of the world as if it were seen from inside the pumpkin. The pumpkin helmet can be removed and placed into the player's inventory. Since worn pumpkins are considered by the game to be armor, they can be enchanted in Creative Mode or through third party tools to make a helmet that acts as armor and yet never takes any damage (since it has no durability). This also works with heads, which won't block the player's view, but looking at Endermen would still provoke them.

When worn as a helmet, the player may look directly at Endermen without consequences, making it useful for going outside at night. However, due to the limited visibility that the pumpkin mask has, it can be a serious drawback to your ability to effectively spot and engage other mobs. The limited visibility may be modified or removed by the use of texture packs or third person view - which, in turn, does have its own drawbacks. You can remove the blur caused by the pumpkin by going into minecraft's jar file, opening the misc file, and editing the pumpkin blur picture by making it transparent.

Pumpkins can be used to make Snow Golems and Iron Golems by stacking 2 blocks of snow/iron, (and also 2 blocks of iron to the side for Iron Golems) and then placing a pumpkin on top as the head. The pumpkin must be placed last or it will not work.

Farming
It is possible to farm pumpkins in the same way as melons; planted pumpkin seeds grow into a central stem that grows until it reaches its maximum size, at which point pumpkins will randomly spawn in vacant dirt/grass next to the stem.

Seeds to start farming can be found in two ways: In chests in Abandoned Mineshafts, or by finding "wild" pumpkins and crafting them into seeds. (Once a farm is started, mature stems can also be harvested for seeds.) When planted in farmland, the seed will produce a central stem that slowly grows until it reaches its maximum size, after which point a pumpkin block will randomly spawn next to it on an adjacent farmland or grass/dirt block. This makes pumpkin farms require somewhat less maintenance than carrot, potato, and wheat farms because you do not have to repeatedly plant after harvesting.

Pumpkins will grow facing 0 (south) in a farm, regardless of where the stem is, but natural wild pumpkins can be found facing any direction. Since pumpkins can grow on both farmland and dirt, there is no reason to till the dirt back to farmland after harvesting a pumpkin, especially since an appearing pumpkin destroys the farmland beneath it. Pumpkin stems will only connect to one pumpkin block, if not already connected to one, they will connect to any pumpkin that grows or is placed next to them. Once connected to a pumpkin, a stem cannot grow another one until the one it's linked to is removed.

Pumpkin stems take around 10 to 30 minutes to fully develop. Bonemeal will cause a pumpkin stem to become fully-grown, but will not produce a pumpkin immediately. Pumpkin stems cannot be grown in The End unless matured by bone meal and they will not produce pumpkins. For more details and farm layout suggestions, see the tutorial. One fairly good layout is shown below.



Trivia

 * The pumpkin is the only headgear that obstructs the player's view.
 * If you use an inventory editor to change a pumpkin's damage value, the pumpkin will have no carving, and you can wear it without the carving. Once placed, it will revert to its normal texture.
 * Regardless of the direction the pumpkin is facing, the upper texture is always oriented the same way.
 * Pumpkins cannot be placed on air, fences, glass, glass panes, flowers, mushrooms, pressure plates, sugar cane, torches, redstone torches, redstone wire, signs, glowstone, ice, pistons, any stairs, iron bars, slabs, sticky pistons, etc. (basically any block that does not take up an entire block (1x1x1) or takes up more space than a block, like a piston)
 * Although pumpkins can spawn on farmland (converting it back to dirt), they cannot be placed onto farmland by the player.
 * If a 1 block high mob is standing next to a pumpkin stem when a pumpkin grows, the mob will suffocate inside the pumpkin or automatically move one block so it's not in the pumpkin. For this reason, it is wise not to place your pets in pumpkin gardens.
 * Undead mobs and Spider Jockeys have a chance to spawn wearing a Pumpkin (or, more rarely, a Jack o'Lantern) on October 31 (Halloween). While Zombies and Skeletons burn normally in daylight, they do not do so when wearing a helmet, and these do count.  Note that the player can not wear a Jack o'Lantern. The mobs will also not drop it if killed.
 * In the Pocket Edition's Prerelease, pumpkins were a placeable block, but were removed before the alpha release, then re-added in 0.8.0. However, they can't be used as a helmet [Yet].