What's the plural form of sea buckthorn? Here's the word you're looking for.
Answer
The noun sea buckthorn can be countable or uncountable.
In more general, commonly used, contexts, the plural form will also be sea buckthorn.
However, in more specific contexts, the plural form can also be sea buckthorns e.g. in reference to various types of sea buckthorns
or a collection of sea buckthorns.