Is it bad to go outside when flowers first bloom when you have asthma?

Depends...: If you are allergic to those flowers blooming, they should be avoided as much as possible. If you are allergic to pollen, stay indoors as much as possible during high pollen count days. The same can be said of poor air quality in general. If none of these things results in bronchospasm for you, then no need to avoid them.

It's not the flowers: Flowers bloom when other airborne plant pollen, especially tree in the spring, is in the air. If a plant is colorful or has a pleasant odor, it is to attract insects for pollination. Tree, grass, ragweed and other allergy causing pollen is wind borne causing symptoms in allergic people when they are exposed.