Іде дощ, так що полив не потрібний.

Yes. Іде is the 3rd person singular of йти / іти, which usually means to go or to walk. But in Ukrainian, just like in some expressions in English, this verb is also used for weather.

So Іде дощ literally feels like Rain is going / coming, but the natural English meaning is It is raining.

You may also see:

• Йде дощ — very common
• Іде дощ — also correct

Both mean the same thing.

Ukrainian often does not use a dummy subject like English it in weather expressions.

Compare:

• English: It is raining
• Ukrainian: Іде дощ

The noun дощ already names what is happening, so no extra subject is needed.

Yes, you can. Ukrainian word order is more flexible than English word order.

Both are correct:

• Іде дощ
• Дощ іде

The version Іде дощ is very natural when simply stating the situation.
Дощ іде can sound slightly more focused on rain itself, depending on context and intonation.

Дощ is in the nominative singular.

It is the grammatical subject of the clause:

• дощ = rain

Even though English uses it in It is raining, Ukrainian uses the noun itself as the subject.

Here так що means so, so that, or therefore, depending on the context.

In this sentence:

• Іде дощ, так що полив не потрібний.

it connects the two ideas:

1. It is raining.
2. As a result, watering is not necessary.

So here так що is best understood as so or therefore.

This is a very important distinction:

• так що = so / therefore / as a result
• тому що = because

So:

• Іде дощ, так що полив не потрібний
  = It is raining, so watering is not needed.

But:

• Полив не потрібний, тому що йде дощ
  = Watering is not needed because it is raining.

They express different logical directions.

Because так що introduces a result clause, and in Ukrainian such clauses are normally separated by a comma.

So the sentence is correctly written as:

• Іде дощ, так що полив не потрібний.

This is standard punctuation.

Полив is a noun meaning watering or irrigation.

It comes from the idea of watering plants, a garden, a lawn, and so on.

Examples:

• полив городу = watering the vegetable garden
• полив газону = watering the lawn

So in this sentence, полив means the act or need of watering.

Потрібний agrees with полив.

Since полив is:

• masculine
• singular
• nominative

the adjective also appears in the masculine singular nominative form:

• полив — masculine singular
• потрібний — masculine singular

So:

• полив не потрібний = watering is not necessary

Yes. Both are possible, and both are natural.

You may hear:

• полив не потрібний
• полив не потрібен

Both mean watering is not needed.

Very roughly:

• потрібний is the full adjective form
• потрібен is a shorter predicative form often used in statements like is needed / is necessary

In everyday speech, не потрібен is extremely common.

Because не with adjectives is often written separately when it simply negates the idea:

• потрібний = necessary
• не потрібний = not necessary

This is the straightforward negation of the adjective.

In practice, spelling with не in Ukrainian can depend on meaning and lexicalization, but in a basic sentence like this, writing it separately is standard and easy to understand.

Yes. Іде is present tense, 3rd person singular.

The whole sentence is in the present:

• Іде = is going / is raining
• не потрібний = is not necessary

So the sentence describes a present situation:

• It is raining now, so watering is not needed now.

A native speaker could definitely say it. It sounds natural, especially in practical contexts like gardening, farming, or everyday conversation.

A few natural variants are also common, for example:

• Йде дощ, так що полив не потрібен.
• Оскільки йде дощ, полив не потрібен.
• Дощ іде, тож полив не потрібен.

Your original sentence is correct and understandable. Some speakers might prefer йде over іде, or не потрібен over не потрібний, but the sentence itself is perfectly good Ukrainian.