When I first learned to crochet my favourite stitch was the granny stitch and by all means it still is. It is amazing the different patterns you can create using one simple stitch.
My favourite granny stitch blanket is the continous granny stitch blanket. It literally is one big massive granny square. You just keep crocheting round until you get the size you like. I mainly make baby blankets with the pattern as I find they are quick and easy to make and you can use any yarn. This project is also a great scrap buster project, as you can keep adding strands of left over yarn and make up so many colour combinations.
Take a look below at some of the continous granny square blankets I have made over the years.
My main yarn choice is acrylic as its easy to wash and can be put in the dryer too. I usually use either a 4mm hook or 4.5mm hook for baby blankets.