When it comes to writing a story, you, as the author, have an amazing amount of control - you choose the rules of your universe, who exists in it, and what exists in it. But it's this last one that I want to focus on specifically, because while it is easy to introduce items into your story, there is an expectation from your reader that everything - down to the petals on the plant - has a meaning.
The name given to this principle is called Chekhov's Gun, and the adage is pretty simple: One must never place a loaded rifle on the stage if it isn’t going to go off. It’s wrong to make promises you don’t mean to keep. What this means in practice is, if you call out a specific object in the scene, but never use that object, you are signalling to the reader this thing will be important, but then letting them down.
If you want a perhaps on the nose example of Chekhov's Gun, you can look to Of Mice and Men, a book you likely (begrudgingly) read in your high school English class. In the novel, Steinbeck introduces Carlson's Luger early in a mundane context, when it is used to put down an old dog; later, the same gun becomes the instrument of the novel's devastating ending.
The obvious exception here is if you are looking to intentionally mislead your reader, such as if you are writing a murder mystery, where it may be beneficial. In this case, you may make reference to a mysterious stain on a carpet, or have a detective note some odd marks on the wall, letting the reader believe they are closing in on the killer before you pull the rug out from under them.
For an example of this trope, you can look to another classic you may have read in school: Agatha Christie's And Then There Were None. She deliberately establishes multiple characters as suspicious throughout, each with a plausible motive, specifically to misdirect the reader from the actual killer.
The other trap you should be aware of and avoid unless you are using it intentionally is Trope Telegraphing. This is the act of revealing to the reader what is going to happen. Examples of this can be obvious, such as your main character proudly proclaiming he aced the test when he hadn't studied the night before, or even as subtle as making it seem the plot is going to resolve on page 100 when there are 200 pages left of your novel.
When done well, Trope Telegraphing can be a fun way to let your reader in on a "secret" that the character may not know yet, however when done unintentionally or overused can feel cliché and cause the reader to lose investment.
This one can be found in perhaps Shakespeare's most infamous play, Romeo and Juliet. The play opens, literally telling you they both die. Shakespeare expertly used this to create dramatic irony, forcing you to wince through the whole play at every near miss knowing what is coming.
The key to using either of these techniques is to use them intentionally. If you are introducing a character or object into your story, make sure you intend to use it, otherwise it should be cut when it comes to editing. For red-herring objects such as those used in mystery novels to misdirect the reader, it can also be helpful to ask your beta readers how they felt about these inclusions after they have read your novel.
And remember, the only difference between a dreamer and an author is the tap of keys or the stroke of a pen.
