J’arrose de peur que la plante dépérisse.

Because je is shortened to j’ before a vowel sound. Since arrose begins with a-, French uses elision:

• je + arrose → j’arrose

This is very common:

• j’aime
• j’habite
• j’écoute

It helps the sentence flow more naturally in pronunciation.

De peur que means for fear that, out of fear that, or sometimes lest in more formal English.

It introduces something the speaker wants to avoid. In this sentence, the idea is:

• I water, for fear that the plant might wither.

So the watering is done because of a feared possible result.

This expression is somewhat formal or literary compared with everyday speech. In casual French, people might express the same idea in a simpler way.

Because de peur que is one of the expressions that normally requires the subjunctive.

The subjunctive is used here because the plant’s withering is:

• not stated as a fact
• only feared
• uncertain or hypothetical

So French uses:

• de peur que la plante dépérisse

rather than the indicative.

This is a very common pattern in French: after certain expressions of fear, emotion, doubt, purpose, or necessity, the subordinate verb goes into the subjunctive.

Dépérisse is the present subjunctive of dépérir.

Here is the relevant subjunctive form:

• que je dépérisse
• que tu dépérisses
• qu’il / elle dépérisse
• que nous dépérissions
• que vous dépérissiez
• qu’ils / elles dépérissent

In your sentence, the subject is la plante, which is third person singular, so French uses dépérisse.

Dépérir means something like:

• to wither
• to waste away
• to decline
• to languish

For a plant, to wither or to fail to thrive is usually the most natural translation.

It suggests gradual weakening rather than sudden death. So la plante dépérisse means the plant might deteriorate, weaken, or wither away.

Very often, yes: after expressions of fear such as de peur que, French often uses an optional ne called the expletive ne:

• J’arrose de peur que la plante ne dépérisse.

This ne does not make the clause negative. It does not mean not.

So these two sentences mean essentially the same thing:

• J’arrose de peur que la plante dépérisse.
• J’arrose de peur que la plante ne dépérisse.

The version with ne is especially common in careful or formal French. Its absence here is not wrong.

Because this is the special expletive ne, not a normal negative ne.

Compare:

• Je crains qu’il ne vienne.
  = I fear that he may come.
  Here, ne does not make it negative.

But real negation would usually need another negative word such as pas:

• Je crains qu’il ne vienne pas.
  = I fear that he may not come.

So in your sentence, if you add ne, it is just a grammatical feature often used after expressions of fear. It does not reverse the meaning.

French can certainly use elle, but using la plante makes the sentence clearer and more self-contained.

Compare:

• J’arrose de peur que la plante dépérisse.
• J’arrose de peur qu’elle dépérisse.

Both are possible. The second version assumes it is already obvious what elle refers to.

A learner may also notice that many French sentences repeat the noun where English might prefer a pronoun. French often does this for clarity.

Yes, a native English speaker may feel that something is omitted. Arroser is usually transitive, and very often you would say what you are watering:

• J’arrose la plante de peur qu’elle dépérisse.

That would be a very natural version: I’m watering the plant for fear that it might wither.

But French can also leave the object unstated if it is understood from context. In that case, J’arrose just means I’m watering or I water.

So the sentence is understandable, though many speakers would naturally include the object.

Because the meaning is slightly different.

• de peur que = motivated by fear of something bad happening
• pour que = in order that / so that

Compare:

• J’arrose de peur que la plante dépérisse.
  The focus is on the feared outcome.

• J’arrose pour que la plante ne dépérisse pas.
  The focus is on the goal: preventing the plant from withering.

Both can make sense, but de peur que specifically highlights anxiety or concern.

Yes, it sounds fairly formal or literary, mainly because of de peur que.

In everyday spoken French, many people would choose a more straightforward wording, such as:

• J’arrose la plante pour qu’elle ne dépérisse pas.
• J’arrose la plante pour éviter qu’elle ne dépérisse.

Your original sentence is perfectly good French, but it has a slightly more elevated tone than ordinary casual conversation.

A rough pronunciation guide is:

zha-ROHZ duh PUHR kuh lah PLAHNT day-pay-REESS

A few points for English speakers:

• J’ sounds like the s in measure
• arrose has a French r, not an English one
• que is pronounced roughly kuh
• dépérisse ends with a hissed -s sound, not a silent ending

The rhythm is also important: French flows smoothly from one word to the next, especially around que la plante.

It has two parts:

1. J’arrose
   = main clause

2. de peur que la plante dépérisse
   = subordinate clause introduced by de peur que

So the structure is:

• main action
  • expression of fear
    • subjunctive clause

You can think of it as:

• I water
  • for fear that
    • the plant might wither

That pattern is useful to remember, because you can build similar sentences with other verbs:

• Je ferme la fenêtre de peur qu’il fasse froid.
• Elle part tôt de peur qu’elle ne soit en retard.