Distinguish between verb+ing as Noun and as Adjective

Question

Verb-ing words can function as nouns, adjective and verbs.

1. Growing plants is my hobby.

2. Growing plants in your back yard need more care.

3. I am growing aromatic plants in my garden.

In the first sentence, “growing” is a noun, in the second, it’s an adjective, and in the last sentence together with “am”, it is a verb in present continuous tense.

Now consider the following 2 sentences

1.) Growing plants in your back yard need more care.

2.) Marketing baby products in the internet world requires a cohesive message to be spread through traditional print and social media.

In 1st sentence, “growing” is the adjective that presents a characteristic of the “plants”. In 2nd sentence, “marketing”, the verb-ing word acts as a noun and forms a big noun phrase “Marketing baby products in the internet world” that is the subject of the sentence.

Now my question is why the verb+ing modifier is different in the two sentences when they have the same structure of Verb+ing modifier+ noun+ prepositional phrase. How i can distinguish between two ? Is there any rule?

Answer 1

You've hit on a problem with gerunds: they can be ambiguous at times, and lead to syntactic ambiguity. From Wikipedia:

Flying planes can be dangerous.
Either the act of flying planes is dangerous, or planes that are flying are dangerous.

Sometimes this ambiguity can lead you into a full-blown garden-path sentence, which forces the reader to reparse a sentence after forming initial assumptions about it. This is what is happening in the following (adapted from your example):

Growing plants in the back yard need more care.

Everything depends on whether the verb in that sentence is going to be need or needs. But you don't know that until you have read the first seven words. I, for one, would be inclined to parse the sentence initially as a gerund, which would mean I read the subject of the sentence as comprising the entire seven words. But when I see that the verb is need, not needs, I have to go back and realign my interpretation with the now obvious facts.

Here are the example sentences showing the different subjects that complement the different verbs (subjects in bold, verbs in bold-italic).

Growing plants in the back yard need water.

Growing plants in the back yard needs water.

Unless you're James Joyce or Shakespeare, it's your job as a writer to avoid ambiguity and multiple interpretations of the same set of words. In which case it would behoove you to recast an ambiguous sentence.