Photo Walk

I’m a member of an all volunteer Master Naturalist group; our local chapter has ~200 members. Our activities range from invasive species removal to education children and adults. I’m thinking about conducting / co-leading a photo-walk at the height of Virgina Blue Bells (Mertensia Virginica) blooming; spring ephemerals native to our area – natural habitat shade, moist woodlands & flood plains.
I’ve a good knowledge of the area and accessibility.
Questions:

• How many folks to accept – limit by free registration?
  
• How long in both distance and time?
• Propose a time of day regardless of “good” light (most often the blooms are located in partial to full shade)?
• How to be inclusive of all photographic levels?
• Lead time for invitation / announcement (prospective dates around April 15)?