While no flowers are considered hypoallergenic, there are varieties that are less potent to people who have allergies. The rule is usually if the bee has to climb into the flower to get to the pollen it is more likely that pollen won’t have as much freedom to contaminate the air that can cause those allergies to bloom. Although most allergens are from the pollen, some are also triggered by fragrances which can come from pollen.
These flowers are the least likely to cause allergic reactions:
Hydrangea
Lilies, asiatic only (anthers have been pulled)
Roses
Orchids – dendrobium, phalaenopsis, mokara, oncidium
Hypericum (coffee, non-blooming varieties)
Carnation
Dahlia
Iris
Tropical flowers – anthurium, heleconia
These flowers have some pollen/fragrance:
Tulips
Daffodils
Chrsanthemums – the double varieties
Gypsophillia – double varieties
Some of the worst culprits are tree pollen and grass pollen.
Here’s a link for some more information: http://ezinearticles.com/?Flowers-For-the-Allergic&id=1857795