Fertiliser for trees

[Mjk86]

just thought id fire this out there to get some advice, I have a small patch of trees that could be doing with some fertiliser, id maybe say 300/400 trees, I was told tree boost would be the ideal one for me but I cant seem to buy it in individual bags. is there anywhere that sell them in small doses an is there a price? I noticed a guy on gumtree selling 50 bags for £50 is this about right?

 

any advice welcome 

 

cheers,

Malks

[daveatdave]

you want inorganic fert for trees do a web search it should com up with something  you really want to test the soil to see if its lacking some of the NPK but if all else fails try pelleted chicken  manure /cow manure