just bought a small one from Asda for £2.00, want to plant for berries. Will this be best in sun or shade, also will my dog be ok if he eats a berry when I'm not looking.
A quick look an the web does indeed show that the berries can be harmful to dogs and other pets, yet the birds seem to eat them ok. Also , though small and probably not having many thorns on them at the moment, as they grow they develop into 1" + thin, long, hard and evil spines that often break off as they pierce your skin, which can often go a bit nasty if you do not get it all out. Think once a dog get its nose prickled they will always avoid it ! Otherwise they do make a nice bush or intruder protective hedge; over 10ft tall if you do not cut them back.
Good avice @ricky101 Pyracanthas prefer full sun or partial shade otherwise the stalks tend to grow at strange angles to seek out light. Still may be worth staking it up though so it starts off growing vertically.
Won't be small for too long! Fabulous plant for wildlife and, as said above, it is known as one of the "Burglar deterrent" plants. With that in mind, when choosing a spot to put it, do think hard! Because, if you change your mind a couple of years down the line, you will be ripped to pieces trying to move it! As for the berries and dogs: it is a back of the border plant, so won't be draped in front of dogs nose in temptations way (I'm assuming?) The birds soon take care of the berries. Which colour berries did you go for? Red, orange or yellow?
Dogs in my experience, will take little notice once it becomes part of the surroundings. Only risk is if it's a young puppy nibbling everything Mine is in full sun & bees adore the small white flowers between now & June.