Želim posijati origano u posudu za cvijeće.

After željeti (to want), Croatian very commonly uses the infinitive:

• Želim posijati origano. = I want to sow oregano.

So this structure is very normal:

• želim ići = I want to go
• želim kupiti = I want to buy
• želim posijati = I want to sow

You can also hear a da + present tense structure in some contexts, but with želim + infinitive, the sentence sounds straightforward and standard.

Not quite.

• posijati = to sow, to plant by seed
• saditi = to plant something like a seedling, young plant, tree, etc.

So if you are putting oregano seeds into soil, posijati is the right choice.

Compare:

• Posijati origano = to sow oregano seeds
• Posaditi origano = to plant an oregano plant/seedling

A learner might also notice sijati. That is the related imperfective verb, while posijati is perfective.

• sijati = to be sowing / to sow in a general or repeated sense
• posijati = to sow successfully / as a completed act

Because želim posijati refers to a single intended action, the perfective verb works well.

Origano is typically treated as an indeclinable noun in Croatian, especially in everyday use. That means it often keeps the same form in different grammatical roles.

So you get:

• origano
• posijati origano
• volim origano
• miris origana may also appear in some usage, but origano is very often left unchanged

For learners, the safest practical point is: in many ordinary sentences, origano stays origano.

This is a very important Croatian pattern.

With u, the case depends on the meaning:

• u + accusative = movement into something
• u + locative = location inside something

Here, the idea is putting/sowing oregano into the container, so there is movement toward the inside. That is why Croatian uses accusative:

• u posudu = into the pot/container

Compare:

• Sijem origano u posudu. = I am sowing oregano into a pot.
• Origano je u posudi. = The oregano is in the pot.

So:

• posudu = accusative singular
• posudi = locative singular

Posudu is accusative singular of posuda.

Basic form:

• posuda = container, pot, vessel

Here is the relevant contrast:

• posuda = nominative singular
• posudu = accusative singular

Because the action goes into the container, the accusative is used after u.

Literally, posuda za cvijeće means something like:

• container for flowers
• in natural English here: flower pot / flower container / planter

The preposition za often means for. After za, Croatian commonly uses the accusative. In this phrase, however, cvijeće looks the same in nominative and accusative, so you do not see a visible change.

So:

• posuda za cvijeće = a container intended for flowers

This is a normal way to describe the function of an object in Croatian.

Compare:

• čaša za vodu = glass for water
• kutija za cipele = box for shoes
• posuda za cvijeće = pot/container for flowers

No, cvijeće is not a regular plural form. It is a collective/mass noun meaning flowers in a general sense.

So although English says flowers, Croatian often uses cvijeće as a single mass noun:

• Volim cvijeće. = I like flowers.
• Posuda za cvijeće. = flower pot / container for flowers

A related singular noun is:

• cvijet = flower

So:

• cvijet = one flower
• cvijeće = flowers / floral vegetation in a collective sense

This is why za cvijeće is perfectly natural.

Yes. Posuda is fairly general: container.

Depending on context, a Croatian speaker might also say:

• tegla / teglica = pot / small pot
• lončanica sometimes refers to a potted plant, not usually the pot itself
• žardinjera = planter / flower box
• lonac usually means cooking pot, so it is less suitable here unless the context is playful or improvised

So if you specifically mean a flowerpot, many speakers might prefer:

• Želim posijati origano u teglicu.

But u posudu za cvijeće is understandable and correct.

The given word order is natural:

• Želim posijati origano u posudu za cvijeće.

Croatian word order is more flexible than English, but different orders can shift emphasis.

For example:

• Origano želim posijati u posudu za cvijeće.
  Emphasizes oregano.

• U posudu za cvijeće želim posijati origano.
  Emphasizes the place/container.

The original version is a neutral, standard order:
I want to sow oregano in a flower pot.

A rough English-friendly guide:

• Želim ≈ ZHEH-leem

  • ž sounds like the s in measure

• posijati ≈ po-see-YA-tee

  • j is like English y

• origano ≈ o-ree-GA-no

• u ≈ oo

• posudu ≈ po-SOO-doo

• za ≈ za

• cvijeće is the trickiest, roughly ≈ TSVYEE-cheh

  • c = ts
  • ć is a soft ch-like sound

The stress can vary somewhat by speaker and region, but this approximation will help you be understood.

It strongly suggests from seed because of posijati.

If you mean putting an already-grown oregano plant or seedling into the pot, Croatian would more naturally use:

• posaditi

So:

• Želim posijati origano u posudu za cvijeće.
  = I want to sow oregano in a flower pot.

• Želim posaditi origano u posudu za cvijeće.
  = I want to plant oregano in a flower pot.

That distinction is useful and very common in gardening vocabulary.