Plant’s beginning to hold strike with fear for marine plant (7)
I believe the answer is:
seaweed
'marine plant' is the definition.
(I've seen this before)
'plant's beginning to hold strike with fear' is the wordplay.
'plant's beginning' becomes 'seed' (I've seen this in another clue).
'to hold' means one lot of letters goes inside another.
'strike with fear' becomes 'awe' (I can't explain this - if you can you should give a lot more credence to this answer).
'seed' going around 'awe' is 'SEAWEED'.
'for' acts as a link.
Can you help me to learn more?
(Other definitions for seaweed that I've seen before include "Coastal plants" , "Eg, kelp" , "Wrack" , "We eased (anag)" , "Marine plant" .)