Raised beds for vegetables

I have just cleared out the raised beds ready for planting this year's veg. I want to put some of it in within the next month but want to put some fertiliser into the soil first. Am I best buying some bagged manure and spreading it across the top and leaving it for a couple of weeks or so and then turn the soil over? Also, is the manure enough, or should I add anything else to the soil?

I have also noticed some snails and baby slugs in the beds. I believe there is a water in product that is safe to use on areas where fruit and veg are growing and also gets the critters underground. Any ideas?

 

i think i would just buy a tub of ckicken pellets and spread them liberally now a couple of weeks ahead of planting. Maybe a handful blood fish and bone too.

As for the slugs, i just disturb them and leave them for the birds to clear up. some say less digginig is better for the soil but im not a digger so dont really know the ins and outs on that.