Poté co přemokříme kořenový bal, začne rostlina vadnout.

Poté co means after, once, or after the point when. It introduces a subordinate clause:

• Poté co přemokříme kořenový bal = after/once we overwater the root ball

It is a bit more formal or written-sounding than some everyday alternatives.

Because Poté co přemokříme kořenový bal is a subordinate clause, and začne rostlina vadnout is the main clause. Czech separates these two clauses with a comma.

So the structure is:

• subordinate clause: Poté co přemokříme kořenový bal
• main clause: začne rostlina vadnout

This is very normal Czech punctuation.

Přemokříme literally means we overwater / we make too wet.

But in Czech, especially in explanations, instructions, or scientific-style statements, 1st person plural can be used in a general sense. It does not always mean a specific group of people. It can feel similar to English:

• if we overwater...
• when you overwater...
• when one overwaters...

So here it is probably a general statement about what happens if someone overwaters the plant.

Because přemokřit is a perfective verb.

In Czech, perfective verbs do not normally have a true present-tense meaning for an ongoing action. Their present forms often refer to a future completed event.

So:

• přemokříme literally has present endings
• but it means something like we will overwater / once we overwater

That is very common in Czech aspect.

The prefix pře- often gives the idea of too much, over-, or excess.

So:

• mokrý = wet
• přemokřit = to make too wet, to soak too much, to overwater

This is why přemokřit is stronger than just zalít (to water) or navlhčit (to moisten).

It is in the accusative singular, because it is the direct object of přemokříme.

We are overwatering what?

• kořenový bal

Because bal is a masculine inanimate noun, its accusative singular has the same form as the nominative singular. So:

• nominative: kořenový bal
• accusative: kořenový bal

The adjective kořenový matches the noun in case, number, and gender.

Literally, it means root ball.

• kořen = root
• kořenový = root-, relating to roots
• bal = ball, bundle, mass

In gardening or botany, kořenový bal is the mass of roots and surrounding soil/substrate.

So this is a standard horticultural expression, not a strange one-off phrase.

This is the verb začít (to begin/start) plus an infinitive.

• začne = will begin
• vadnout = to wilt

So:

• začne vadnout = will begin to wilt

This is a very common Czech pattern:

• začít + infinitive

For example:

• začne růst = will begin to grow
• začne klesat = will begin to fall/drop
• začne usychat = will begin to dry out

Because vadnout is imperfective and describes the process of wilting.

After začít (to begin), Czech usually prefers an imperfective infinitive, because you are starting a process:

• začne vadnout = it will begin wilting / begin to wilt

By contrast, uvadnout is perfective and focuses more on reaching the result of becoming wilted.

So začne vadnout sounds natural because it means the plant starts going into that state.

Czech word order is more flexible than English word order.

Here:

• začne rostlina vadnout

is perfectly natural. The verb comes first in the main clause because the sentence begins with a subordinate clause, and Czech often places the finite verb early in the main clause.

You could also say:

• Poté co přemokříme kořenový bal, rostlina začne vadnout.

That version may feel a little more neutral to some learners because the subject comes before the verb, but both are understandable and natural.

Sometimes yes, but the nuance changes.

• Poté co = after / once
• když = when, and sometimes if depending on context

So:

• Poté co přemokříme kořenový bal...
  = after/once we overwater the root ball...

• Když přemokříme kořenový bal...
  = when/if we overwater the root ball...

Poté co is more specifically about sequence in time: first the overwatering, then the wilting begins.

You might also hear:

• jakmile = as soon as

which is another close alternative.

Because Czech has no articles like English a/an/the.

So rostlina can mean:

• a plant
• the plant
• sometimes even plants in general in a generic statement

You understand which meaning is intended from context.

In this sentence, it could mean either:

• a specific plant already being discussed, or
• a plant in general as an example

English has to choose an article, but Czech does not.

Most likely it is stating a general rule or typical consequence.

Several things point in that direction:

• the generic we in přemokříme
• the lack of articles in Czech
• the scientific/gardening context
• the causal sequence: overwatering leads to wilting

So it reads like a general horticultural statement: if/once the root ball is overwatered, the plant starts to wilt.