fertilisers

For trees I tend just to mulch with manure or compost, and I make compost to dig into the plot.  Everything else gets a pretty simple regime 

If you want a general purpose feed, Growmore is cheap, covers the bases and easy to use.   I use pelleted chicken manure a lot.  This is high nitrogen, so is good for getting veg growing.

In the greenhouse, I tend to have 2 liquid feeds on hand - a tomato feed for anything fruiting and a general one for anything growing.  The general liquid feeds for veg are high nitrogen as well.

Leaves and shoots need nitrogen
Roots need phosphorus
Fruits need potassium

This is the NPK referred to on fertilizers and what the numbers on the pack indicate.  One that said 20-10-10 would have twice as much nitrogen as the other 2 nutrients.

Don't buy lots of things for different jobs.  If you look at the NPK numbers on the pack, you'll see a lot of stuff sold for strawberries, or green veg or various other things all actually have the same content 

We have foxes patrolling our site, so Fish, Blood and Bone sends them into a frenzy of digging    Its good stuff though if you can get away with it 

BTW, if you have a dog, they can sometimes be fascinated by chicken manure pellets and try and eat them.   My neighbour was chucking them around like I do, until she noticed her dog hoovering them up behind her -  bleeuuuggghh 

To add to this thread,

Organic fertilisers, on the whole, tend to be more 'slow release' then conventional fertilisers. This does give you a bit of flexibility if you know that you are going to be away when you want N, P or K actually available to the plants. I've been known to mix a half dose of prilled urea and a half dose of blood to get an extended action of N on 'hungry' crops like corn if I know that I'm away for a month at precisely the wrong time.