Ružmarin raste u blizini prozora.

Because u blizini is followed by the genitive case. The basic form is prozor meaning window, but after u blizini it becomes prozora.

So:

• prozor = nominative, dictionary form
• prozora = genitive singular

This is a very common pattern in Croatian:

• u blizini kuće = near the house
• u blizini škole = near the school
• u blizini prozora = near the window

Yes, u often means in or into, but here it is part of the fixed expression u blizini, which means near or more literally in the vicinity of.

So you should learn u blizini as a set phrase:

• u blizini prozora = near the window

This does not mean the rosemary is literally inside the vicinity in some strange way; it is just the normal Croatian expression for near.

Raste is the 3rd person singular present tense of the verb rasti, meaning to grow.

So:

• ja rastem = I grow / am growing
• ti rasteš = you grow / are growing
• on / ona / ono raste = he / she / it grows / is growing

Because ružmarin is singular, the verb is also singular: raste.

It can mean either, depending on context. Croatian present tense often covers both ideas that English separates into simple present and present continuous.

So Ružmarin raste u blizini prozora could mean:

• Rosemary grows near the window
• Rosemary is growing near the window

Usually the wider context tells you which is more natural.

Ružmarin is masculine. One strong clue is that it ends in a consonant, and many Croatian nouns with that ending are masculine.

So in grammar terms:

• ružmarin = masculine singular noun

That matters when adjectives or pronouns agree with it, for example:

• svježi ružmarin = fresh rosemary

A helpful approximation is roozh-ma-rin.

A few pronunciation notes:

• ž sounds like the s in measure or the g in genre
• r is rolled or tapped more than in most English accents
• u is like oo in food
• Croatian spelling is quite regular, so words are usually pronounced as written

So Ružmarin is pronounced roughly ROOZH-ma-rin.

Because Croatian does not use articles like English a and the.

So:

• prozor can mean a window or the window
• ružmarin can mean rosemary or the rosemary

The exact meaning depends on context. English requires an article, but Croatian usually does not.

Yes. Croatian word order is more flexible than English word order, because case endings show the grammatical relationships.

The basic sentence:

• Ružmarin raste u blizini prozora.

But you could also say:

• U blizini prozora raste ružmarin.

This version puts more focus on the location first: Near the window, rosemary grows / is growing.

Even though word order can change, the original order is very natural and neutral.

Yes. Both are correct and natural.

• u blizini prozora = near the window
• blizu prozora = near the window

Both are followed by the genitive, so you still say prozora.

A small difference:

• blizu is often a bit shorter and more direct
• u blizini can sound a little more descriptive or formal

Yes. It functions as a location phrase, telling you where the rosemary grows.

Its parts are:

• u = preposition
• blizini = noun meaning vicinity / nearness, here in the locative form after u
• prozora = genitive singular, because blizina takes the genitive for the thing that is near

So literally, the phrase is something like:

• in the vicinity of the window

But in normal English, you translate it simply as near the window.

The basic form is blizina, meaning nearness, closeness, or vicinity.

In the sentence, it appears as blizini because after u in a location expression, this noun is in the locative singular:

• blizina → basic form
• u blizini → in the vicinity / nearby

So the structure is:

• u
  • locative = u blizini
• then the thing being referred to is put in the genitive: prozora

No. It is capitalized here because it is the first word of the sentence.

In the middle of a sentence, the common noun ružmarin would normally be lowercase:

• Volim ružmarin. = I like rosemary.

Only proper names are regularly capitalized in Croatian, just as in English.