In August I am planning to spend 4 nights in Florence, 3 nights in Trieste and 3 nights in Venice. To get away from the crowds as much as possible, would you recommend staying outside each of these areas as a base? Any areas you would recommend as must-see's in these areas? More into natural beauty and crafts rather than museums, etc.
Thanks!

If you're not interested in "museums etc" and I assume that you include art galleries, then I'd miss out Florence altogether. The city's attractiveness is architecture and galleries, museums.

Venice is similar in its appeal, apart from the lace and glass available on Murano and Burano. Trieste is a large city and not a natural beauty.

If you want to see wildlife and scenery, then cities are not the best destination, but if you want to see the cities yet stay elsewhere, the cost of getting in and out each day will push up your budget.

I can't speak for Trieste, but Florence and Venice become much more enjoyable in the evenings, when day trippers and cruise ships passengers leave. If you did not stay IN those cities, you would miss the most enjoyable time of day for those who do not like crowds.

In Florence, you might look at accommodations in the Oltrarno (across the river from the historic center). Or perhaps consider Fiesole, which is a commune outside of Florence, bu accessible by bus to the city (30 min?).

In Venice, many people would suggest staying outside of the busy San Marco area and considering Dorsoduro or San Polo.

Rubicund makes sense--those are definitely cities where museums are generally a big draw. So my recommendations are if, after reconsidering, you still want to visit these places, you will need a strategy for choosing where to stay.

Sorry--one last thing. In August, these cities will likely be hot and muggy. Smaller towns in the countryside (in accommodations with air conditioning) might be more enjoyable.

I've stayed on Lido and found the time spent getting back to Venice on the Vaporetto was not worth the savings.

Whatever decision you make, you'll want to consider the transit time to see the sites you are interested in.