Challenge: April field
Word Count: 100
A Bubblehead charm would allow Severus to approach the flowers and possibly gather samples, but eventually the air would run out. Renewing the charm would force him to drop the protective field to bring in fresh air, and of course that would mean pollen. Muggle allergy medicines were equally problematic; the only ones that worked made him drowsy enough that he might as well fall asleep in the midst of the field, while the ones that allowed him to function were ineffective.
The only remedy that might, might, work, was Hidalgo Moriarty's Patented Sneeze-B-Gone powder...
Which gave Severus hives.