Vi planter plantene ut i morgen.

Here, planter is a verb.

After the subject vi (we), Norwegian normally expects a finite verb, so Vi planter ... means We plant / We are planting / We’re planting depending on context.

It can also be a noun form in other contexts:

• en plante = a plant
• planter = plants

So the form planter can be either a verb or a noun, but in this sentence it is clearly the verb.

Plantene is the noun the plants.

It comes from:

• en plante = a plant
• planter = plants
• plantene = the plants

So:

• planter = verb here
• plantene = definite plural noun

A very literal breakdown is:

• Vi = we
• planter = plant / are planting
• plantene = the plants
• ut = out / outdoors
• i morgen = tomorrow

Because Norwegian uses endings to show definiteness.

• planter = plants (indefinite plural)
• plantene = the plants (definite plural)

So if you are talking about specific plants that both speaker and listener know about, plantene is the natural choice.

This is one of the big differences from English: Norwegian often puts the at the end of the noun instead of using a separate word.

Ut means out or outdoors.

In this sentence it gives the idea of moving the plants outside or planting them out in their final place. In gardening, plante ut often means something like plant out or transplant outdoors.

So:

• plante = plant
• plante ut = plant out / put out to grow outside

If you removed ut, the sentence would sound more general. With ut, it sounds more specifically like taking the plants outside or planting them into the ground/outdoor bed.

Because Norwegian very often uses the present tense for the future when the time is already clear.

Here, i morgen tells you the action is in the future, so planter is perfectly natural.

This is similar to English sentences like:

• We leave tomorrow.
• I start work on Monday.

So Vi planter plantene ut i morgen is a normal way to talk about a planned future action.

Because Norwegian usually does not use a special progressive form the way English does.

English distinguishes:

• we plant
• we are planting

Norwegian often just uses the present tense:

• vi planter

The exact meaning depends on context.

For example:

• Vi planter nå. = We are planting now.
• Vi planter i morgen. = We’re planting tomorrow / We plant tomorrow.

So Norwegian relies more on time words like nå (now) or i morgen (tomorrow) than on a special verb form.

No. You do not need skal.

Because i morgen already makes the future clear, Vi planter plantene ut i morgen is complete and natural.

But you can say:

• Vi skal plante plantene ut i morgen.

That version can sound a little more like:

• a plan
• an intention
• something you are going to do

So both are possible, but the sentence without skal is very normal.

Yes, you may also hear Vi planter ut plantene i morgen.

With words like ut, Norwegian word order can vary, especially when ut is felt either as:

• a particle closely tied to the verb, or
• a directional adverb meaning out/outside

The given sentence, Vi planter plantene ut i morgen, is natural and understandable.

A useful thing to remember is that with a pronoun, Norwegian strongly prefers:

• Vi planter dem ut i morgen.
  not
• Vi planter ut dem i morgen.

So the sentence you were given is a good model, and ut placement is one of those areas where you will also notice variation in real Norwegian.

Yes. Norwegian time expressions are fairly flexible.

You can say:

• Vi planter plantene ut i morgen.
• I morgen planter vi plantene ut.

Both are correct.

If you put I morgen first, Norwegian follows the verb-second rule, so the verb must come right after it:

• I morgen planter vi ...

You cannot say:

• I morgen vi planter ...

So the original sentence has a neutral, common word order, but fronting i morgen is also very natural.

Yes. In modern Norwegian, i morgen is normally written as two words.

So the standard spelling is:

• i morgen

Learners sometimes expect one word because English has tomorrow, but Norwegian keeps it separate.