Bulbmom - our school just sold spring bulbs this past sept in place of our usual mums. We ordered a lump sum of about 5 different types of bulbs from dutchmillbulbs.com. Cost is 2.50/Selling price $5.
The co's suggest taking orders but that wasn't our plan, and they sold fairly quickly over a weekend. We did find that the more unusual bulbs sold out faster than the usual tulips and daffodils.
They came packaged in netting, and we downloaded pictures to put on posters, so that people could see what they will look like. This spring they bloomed beautifully. Good luck with your sale!
