Hi,
All plants have a feeding period and this is part of the planting prep,
IF when you plant anything "And "shrubs trees etc come into this more than annual plants, you need to ensure the space your going to plant in is ready with slow acting food and i use the F.B.B mix (fish /blood /bone)
a good compost and soil mixed and a drainage.

If you provide such as ive listed the rain will help this mix break down and slowly feed the plant and stop the plant gettingdrainage problems,
Once a week a feed of a liquid fertilizer wont do it any harm until the end of the growing season after that it wont need any feed from you as the F.B.B. will continue to slow feed the roots.
I use comfrey to feed my plants (home made) .

Plants/shrubs/bulbs etc are much the same as humans they need food /water/ light if they're lacking in any of these they become weak or dead the same as humans.

Is fish/blood/bone alkaline, So not suitable for acid loving plants?

Acers do not need acidic soil. Some prefer it, but ordinary compost is fine. Bonemeal is alkali but it does not neutralise acidic soil - it does not work that way. If you feel like it, then a liquid ericacious feed is available and that gives the Iron and other nutrients.