Advice needed on re-fertilising!!

I'm quite a new gardener and need expert advice. About two years ago, when I moved into my new house, I put various shrubs into the borders, plus a couple of fruit trees. I also planted cuttings which seem to have survived - so far. But I made a bit of a mistake.

The problem is that, with hindsight and subsequently reading tips, I think I should have prepared the soil better before putting plants into the ground. I should have lined the bottoms with rich, crumbly compost etc, but I didn't! However I don't want to dig them out now and risk killing them so what can I do to improve the soil around cuttings/shrubs etc without actually removing them?? Any treatments/fertiliser regimes to recommend???

 

Personally I would lightly fork in well rotted manure this will help with feeding and also act as a mulch and will work its way down into the lower layers.

 

Manure or compost on the top - as lazydog says, lightly fork it in. You could add in some blood fish and bone as a slow release fertiliser.

Our friends the earthworms will eventually pull the compost/manure down into the soil, so I do it annually

 

Yup, mulch. I put 2" - 3" on well rotted manure on my shrub border (planted about 3 years earlier) last Summer and the ground is already in much better heart. I didn't fork it in, but planting out additional plants this spring, and needing to stick a fork in deeply to get some Dandilions out, and the like has the effect of mixing it in a bit.

General purpose fertilizer ("Growmore") around the plants would help. You could use a Tomato fertilizer when the plants are flowering (start a few weeks before they flower)