Learn Dutch: Ze zullen die prachtige exotische orchideeën wel in de kas zetten. - They will probably put those beautiful exotic orchids in the greenhouse.

In Dutch, subjective opinions (like prachtige) almost always come before objective traits, origins, or categories (like exotische). Think of it as moving from your personal feeling to the hard, unchangeable facts about the noun.

What is the word wel doing in this sentence?

Here, wel works together with the verb zullen to express probability or expectation. While zullen normally just means will, adding the modal particle wel softens the sentence to mean will probably or I assume they will.

Why do both prachtige and exotische get an -e at the end?

Because orchideeën is a plural noun. Plural nouns always get the -e ending on attributive adjectives (adjectives placed right before the noun), regardless of whether their singular form is a de or het word.

Why does orchideeën have a trema (two dots) instead of just adding -en?

The singular noun is orchidee. If you simply added -en, it would be spelled orchideeen, which would look like one long, confusing vowel sound. The trema on the final ë shows that a new syllable starts there, helping you pronounce it correctly.