אם היו לנו עוד עציצים במרפסת, היינו משקים אותם כל בוקר.

Because Hebrew often uses past-looking forms to express a hypothetical or unreal condition.

So in this sentence:

• אם היו לנו... = if we had...
• היינו משקים... = we would water...

This is similar to English, which also uses past forms for unreal situations: If we had more plants, we would water them. It does not mean that this really happened in the past.

Hebrew usually expresses possession with יש / אין / היה / היו + ל־.

Literally, היו לנו עוד עציצים is something like:

• there were
• to us
• more potted plants

So Hebrew says there were to us, where English says we had.

A few comparisons:

• יש לנו עציץ = we have a plant / pot
• היה לנו עציץ = we had a plant / pot
• היו לנו עציצים = we had plants / pots

Because היה / היו agrees with the thing that exists or is possessed — here, עציצים, which is plural.

So:

• אם היה לנו עוד עציץ = if we had one more potted plant
• אם היו לנו עוד עציצים = if we had more potted plants

It does not agree with לנו (to us). It agrees with עציצים.

These express different kinds of conditions:

• אם יש לנו עוד עציצים... = if we have more potted plants...
  This sounds like a real present possibility.

• אם יהיו לנו עוד עציצים... = if we have / get more potted plants...
  This points to the future.

• אם היו לנו עוד עציצים... = if we had more potted plants...
  This is hypothetical/counterfactual — it suggests that in reality, we do not have them.

So your sentence is not just talking about the future; it is talking about an unreal situation.

Here עוד means more or additional.

So:

• עוד עציצים = more potted plants
• עוד עציץ = another / one more potted plant

In other contexts, עוד can also mean still or again, but here it clearly means additional.

עציצים is the plural of עציץ.

Depending on context, עציץ can mean:

• a flowerpot / plant pot
• a potted plant

In this sentence, since you water them, the most natural English meaning is potted plants.

Because היינו משקים is the form Hebrew often uses here for a conditional or habitual idea.

Compare:

• השקינו אותם = we watered them
  a simple past action

• היינו משקים אותם = we would water them / we used to water them
  a repeated, habitual, or conditional action

In this sentence, because it follows אם היו לנו..., it means we would water them.

Structurally, this is:

• היינו = we were / would be
• משקים = the participle watering

Together: היינו משקים.

Because the participle agrees with the subject, which is we.

In Hebrew, first-person plural does not have its own special participle form, so Hebrew uses:

• masculine plural as the default or mixed-gender form: היינו משקים
• feminine plural if the speakers are all female: היינו משקות

So if a group of women said this, they could say:

• אם היו לנו עוד עציצים במרפסת, היינו משקות אותם כל בוקר.

אותם means them and is the masculine plural direct object pronoun.

It refers back to עציצים, which is masculine plural. That is why Hebrew uses אותם.

Compare:

• masculine plural: אותם
• feminine plural: אותן

So:

• היינו משקים אותם = we would water them

Not normally in this sentence.

Once Hebrew replaces the noun עציצים with a pronoun, it needs the object pronoun:

• היינו משקים אותם = we would water them

If you leave out אותם, the sentence feels incomplete, because משקים usually needs an object here: you water what?

You could repeat the noun instead:

• היינו משקים את העציצים כל בוקר = we would water the plants every morning

Because כל + time word is the normal way to say every ... in Hebrew.

So:

• כל בוקר = every morning
• כל יום = every day
• כל שבוע = every week

By contrast:

• בבוקר = in the morning

So:

• היינו משקים אותם בבוקר = we would water them in the morning
• היינו משקים אותם כל בוקר = we would water them every morning

In Hebrew, ב־ is broader than English in.

With places like מרפסת, Hebrew says במרפסת, but natural English usually says:

• on the balcony

So you should not translate ב־ mechanically as in every time.

In normal unpointed Hebrew spelling, במרפסת can represent either:

• בְּמרפסת = on/in a balcony
• בַּמרפסת = on/in the balcony

When Hebrew is written without vowels, both look the same: במרפסת.

So the article is not missing; it is just not separately visible in regular spelling. Context tells you whether it means a balcony or the balcony.

Yes. Hebrew can also say:

• היינו משקים אותם כל בוקר אם היו לנו עוד עציצים במרפסת.

That means the same thing.

Putting the אם clause first is very common and makes the condition feel prominent:

• אם היו לנו עוד עציצים במרפסת, היינו משקים אותם כל בוקר.

Yes, that is the usual implication.

Because the sentence uses the counterfactual pattern:

• אם היו לנו... היינו...

it normally suggests:

• we do not have those extra potted plants
• therefore, this watering routine is hypothetical

So the sentence is understood as If we had more potted plants on the balcony, we would water them every morning — but in reality, we do not.