'During the growing period before budding I fill hole with nitro fert, then during budding dig up the soil and take out nitro soil and fill with high phosp fert and let it flower?' (just out of interest how do you lot do that little quote box thing?)
Anyway, you don't fill the hole with fert, you fill the hole with soil. You add fertilizers to the soil, get it. So you buy some ferts, dilute the reccomended amount on bottle to water and water plant. Don't worry you won't have to take out all the soil.