Up to $5,000 of start-up costs and up to $5,000 of organizational costs may be deducted in the year your business opens. Start-up costs are things like market research, acquiring suppliers, and other expenses of that nature. Organizational costs are expenses like lawyer and accountant fees in order to set up the structure of your business, which is more common in corporations and partnerships than sole proprietors. If you paid to get an LLC in your state, this would be an example of an organizational cost. The remainder above $5,000 is amortized over 15 years, meaning you will get about 1/15 of the amount deducted in each year.
Education expenses needed to start a business are not eligible deductions. The IRS states "Education expenses you incur to meet the minimum requirements of your present trade or business, or those that qualify you for a new trade or business, aren’t deductible. This is true even if the education maintains or improves skills presently required in your business."
Ongoing education expenses would be deductible. So, if you took business classes and floral arranging classes in order to be licensed in your state, those would not be deductible. However, if you took continuing education to learn new techniques or as required by a license you held after you were open, those would be deductible.
As for the flowers you purchased for the photoshoot, I think supplies might be a more appropriate category. Advertising would be more for expenses you pay to run your ads in magazines or online, etc.
