It’s very nice that you’re thinking of giving a bonus to a home health worker. This is a thoughtful gesture of appreciation for someone who’s cared for someone special to
you. I don’t think there’s one clear answer to the question of what’s a reasonable bonus. This depends on several factors including your finances and how long the worker was on the job. Remember; “It’s the thought that counts.” You don't need to be extravagant, especially if you can’t afford this. A few things come to mind: You could give one month’s salary (this would be generous); two weeks salary; or a gift certificate to a store or restaurant the worker likes (for whatever amount you can afford).
Another nice gesture is to offer to write a letter of recommendation for the worker, and/or give permission to use you as a reference.