mrpopstar
Sparkly Dude
This would not influence the ability check relevant to the task, it would increase the difficulty of the task.I can easily see a situation where someone hid an item in a potted plant, and then moved other plants in front of that one to create a disadvantage for future searchers.
In other words, you would not modify the seeker's ability check with disadvantage, you would raise the Difficulty Class of finding the hidden item.