A good question.
A local answer.

Account for distance after several hours at the event and any mobility needs.

Check the current Floriade venue and travel route from the exact apartment address before choosing by an old review.

Check the current Floriade location, dates and transport arrangements for the travel year rather than relying on an older forum map.

Check the current opening season and ticket details; bloom timing and availability change by year.

Check each event's current dates, ticketing and bloom updates; old forum prices are not useful for a new season.

Map the actual event entrance to the museum rather than measuring park-to-park distance; the walk includes open lakeside stretches.

Allow time to walk the whole event rather than arriving only for a quick photo.

Keep a second city day for museums or lakeside walks rather than assuming the festival requires a second full entry.

Check the current event's official parking and access map, because temporary closures can change the best approach.

Choose a base that keeps meals and children's downtime easy, even if it is not directly beside the flowers.

Check the current daily program and weather before choosing the time; a talk or performance may make one period more appealing.

Check the festival's current accessibility map, seating, accessible transport and mobility equipment before choosing a date.