Jeśli jutro będzie ciepło, włożymy kolejne nasiona do ziemi obok tarasu.

Yes. Jeśli and jeżeli both mean if.

In everyday speech, jeśli is usually a bit more common and natural. Jeżeli can sound slightly more formal or emphatic, but in most contexts they are interchangeable.

So these are both fine:

• Jeśli jutro będzie ciepło, włożymy kolejne nasiona do ziemi.
• Jeżeli jutro będzie ciepło, włożymy kolejne nasiona do ziemi.

Because Polish often uses an impersonal structure for weather and general conditions.

• jest ciepło = it is warm
• będzie ciepło = it will be warm

Here, ciepło is not an adjective agreeing with a noun. It functions more like warmly / warm in an impersonal weather expression.

You use this pattern for many weather or environmental statements:

• Jest zimno. = It is cold.
• Było ciemno. = It was dark.
• Będzie gorąco. = It will be hot.

If you said ciepły / ciepła / ciepłe, that would normally describe a specific noun:

• dzień jest ciepły = the day is warm
• woda jest ciepła = the water is warm

Yes. Będzie is the 3rd person singular future form of być (to be).

In this sentence:

• jutro będzie ciepło = tomorrow it will be warm

Because the sentence is about tomorrow, Polish uses the future tense.

A few related forms:

• jest = is
• było = was
• będzie = will be

So:

• Dziś jest ciepło. = Today it is warm.
• Wczoraj było ciepło. = Yesterday it was warm.
• Jutro będzie ciepło. = Tomorrow it will be warm.

Włożymy is future in meaning.

It comes from the perfective verb włożyć (to put in, insert, place into). In Polish, perfective verbs do not normally have a present tense referring to an action happening now. Their present-looking forms actually refer to the future.

So:

• włożymy = we will put / we will place

This contrasts with the imperfective verb wkładać:

• wkładamy = we are putting / we put
• będziemy wkładać = we will be putting

Why use włożyć here? Because the sentence describes a completed action in the future: once the weather is good, we will put the seeds into the ground.

Both can work, but they are not identical.

• włożyć = to put in, place into
• wsadzić = to stick/put into, often a bit more physical or colloquial

For seeds, Polish speakers very often say things like:

• wsadzić nasiona do ziemi
• włożyć nasiona do ziemi

Both are understandable. Wsadzić can sound a little more natural in gardening contexts to some speakers, while włożyć is perfectly correct and straightforward.

If you want a more specifically gardening verb, you may also hear:

• zasiać nasiona = to sow seeds

But that is a different verb structure from the sentence you were given.

Because nasiona is the direct object of włożymy, so it is in the accusative case.

However, for many neuter plural nouns, the accusative plural looks the same as the nominative plural. That is what happens here.

Singular and plural:

• nasiono = seed
• nasiona = seeds

In this sentence:

• włożymy co? → kolejne nasiona

So kolejne nasiona means more / additional / next seeds.

Also note:

• kolejny can mean next, another, or subsequent, depending on context.
• Here kolejne nasiona suggests more seeds or the next batch of seeds.

Because the phrase do ziemi means into the ground/soil, and the preposition do requires the genitive case.

• ziemia = earth, ground, soil
• genitive singular: ziemi

So:

• do ziemi = into the soil / into the ground

This fits well with a movement meaning:

• włożyć coś do ziemi = to put something into the ground

Compare:

• w ziemi = in the ground / in the soil
  This often describes location rather than direction.
• do ziemi = into the ground
  This emphasizes movement inward.

So in this sentence, do ziemi is the natural choice because the seeds are being placed into the soil.

Because obok takes the genitive case.

• taras = terrace / patio
• genitive singular: tarasu

So:

• obok tarasu = next to / beside the terrace

Other examples with obok:

• obok domu = next to the house
• obok szkoły = next to the school
• obok ogrodu = next to the garden

This is a good preposition-case combination to memorize:

• obok + genitive

Yes. Polish word order is more flexible than English word order.

The original sentence:

• Jeśli jutro będzie ciepło, włożymy kolejne nasiona do ziemi obok tarasu.

You could also say:

• Włożymy kolejne nasiona do ziemi obok tarasu, jeśli jutro będzie ciepło.

Both are correct.

The version with Jeśli... first sounds very natural because it sets up the condition before the result.

Polish word order can shift for emphasis, rhythm, or style, but the original version is a very standard and natural one.

Because Jeśli jutro będzie ciepło is a subordinate clause introduced by jeśli (if).

In Polish, subordinate clauses are normally separated by a comma.

So:

• Jeśli jutro będzie ciepło, włożymy kolejne nasiona do ziemi obok tarasu.

This is the same idea as in English:

• If it is warm tomorrow, we will put more seeds into the ground beside the terrace.

When the if-clause comes second, Polish still uses a comma:

• Włożymy kolejne nasiona do ziemi obok tarasu, jeśli jutro będzie ciepło.

Here it means soil or ground.

The Polish word ziemia can mean several related things:

• Earth as the planet
• ground
• land
• soil

In a gardening sentence like this one, do ziemi clearly means into the soil / into the ground.

So even though the dictionary may give several meanings, context makes the intended meaning clear.

It can often be translated as either terrace or patio, depending on the context.

In Polish, taras usually means an outdoor area attached to a house or building, often paved or raised. In English, the best translation may be:

• terrace
• patio
• sometimes deck, depending on the structure

So obok tarasu could be understood as:

• next to the terrace
• next to the patio

The exact English word depends on what the place actually looks like.

Usually, for standard Polish, jeśli is the safer and more neutral choice for if.

• Jeśli jutro będzie ciepło... = standard, clear, neutral

In some contexts and regional or colloquial usage, jak can be used with a meaning similar to if/when, but it can sound less standard or may create ambiguity for learners.

So if you are learning Polish, it is best to use:

• jeśli
• or jeżeli

until you get more comfortable with informal patterns.