Learn Hardcore Turkish: Çiftçi tarlada taze sebze dikiyor. - The farmer is planting fresh vegetables in the field.

In Turkish only definite/specific direct objects get the accusative -(y)i suffix.
Here taze sebze (“fresh vegetables”) is indefinite/general, so it stays unmarked.
If you meant “the fresh vegetables” (specific ones), you’d say taze sebzeyi dikiyor.

What is the verb dikiyor, and what does the -iyor part mean?

dikiyor consists of the root dik- (“to plant,” “to erect”) + the present continuous tense suffix -iyor for third-person singular.
So dikiyor = “he/she/it is planting” (or “plants” in a habitual sense).

What is the difference between dikmek and ekmek?

Both verbs can mean “to plant/sow,” but:
• ekmek is generally “to sow seeds” (grains, cereals).
• dikmek is “to plant seedlings, young plants, trees.”
Since vegetables are often transplanted as seedlings, dikmek is more natural here.

Why is there no article like “the” or “a” before Çiftçi? Does Turkish have articles?

Turkish does not use separate words for “a” or “the.”
• Indefiniteness/definiteness is shown by context or, for objects, by the accusative -i suffix.
• Subjects and nouns stand alone without an article.

Why does the adjective come before the noun in taze sebze?

Turkish adjectives always precede the noun they modify and do not agree in number or case.
So taze (fresh) comes before sebze (vegetable), making taze sebze.

What is the basic word order of this sentence, and can it be changed?

The default order here is:
Subject – Locative adverb – Object – Verb
Çiftçi (S) tarlada (locative) taze sebze (O) dikiyor (V)
Turkish word order is fairly flexible, but the verb usually comes last.

What exactly does tarla mean? How is it different from alan?

tarla specifically means a cultivated field used for farming or agriculture.
alan is a more general term meaning “area,” “space,” or “open ground.”