Why don't my pumpkins grow (Minecraft PE / iOS)?

These plants that are fully grown do not continue to grow. No pumpkins form

I just planted the small plants, but they don't grow either

: - /

Does anyone know why?

You still need a free space to the left or right of it.

But I thought you had to water it? But thanks!

Irrigation is 5 or 6 fields wide from where the water is, the water does not have to be right next to the plant.

Use bone meal on all plants to make sure they are fully grown.

Put a torch nearby.

Next to the plant there must still be a free block with soil or a log. (It is already the case)

Water extends 4 blocks further than it says. So it doesn't have to be right next to the plant.

This usually happens when they have too little space, which can be the case here because they are all close together, they grow one to the side per your own seed block. Legmal one for every nine square fields so that there's always at least one block distance between two

You have to water it. You only need a free block on one side

Water can also be two fields further and does not have to be right next to it.

Because there's water next to it.

A single block of water irrigates a 9x9 area around it. So 4 blocks in each direction, also diagonally. So you only need a single block of water for your carrots AND the pumpkins. Would be enough to water everything.
When a pumpkin / melon grows, it tries to grow next to the stem in a random direction. However, 3 of the 4 directions are occupied for you. Of water, or of other seeds. Is it only growing every fourth attempt. And there's such an attempt. It takes one hour every 15 minutes.

Here are a few good designs. If you are always there to harvest, this is best at the top right. If you only harvest the pumpkins every few hours, use the one in the middle on the left.