If you will be there on a Sunday, we love the Wat Thai temple market in Tampa. Be there by 10 am for the best selection. From there, you can go to St Pete and see the Dali Museum, Sunken Gardens, or the Chiluly installations. We have never been to the Lowry Park zoo but did enjoy the aquarium downtown Tampa.
Winter Park is a great place to visit. The Morse Museum with Tiffany glass is free on Fridays in April. Stop at 4 Rivers bbq for lunch and spend the afternoon at Harry P Leu Gardens. The Orlando Science Museum and Orlando Art Museum are near Harry P Leu gardens and can be nice depending on what special exhibits are there. Stop by Sister Honeys near downtown for some great pies and baked goods.
Another garden we like is Bok Towers Garden in Lake Wales. The house is best at Christmastime, but the gardens are always a nice place to walk. Take the free tour of the grounds.
We love lunch at the Columbia in Celebration. We get the infamous half 1905 salad with either black bean soup or half a Cuban sandwich.
The sweetest oranges ripen in April. Head to Showcase of Citrus and get some Valencia oranges. They make the best juice.
Make sure to check websites since many place require advanced reservations.