Catch an early morning flight from Florida (MIA or Orlando) to San Juan, Puerto Rico. Flights are typically around $200-300 per person round trip if booked in advance.
Stay at a budget-friendly beachfront hotel like Serafina Beach Hotel offering great access to Isla Verde Beach with ocean views and cozy rooms, perfect for couples.
Head east for about 45 minutes to El Yunque, the only tropical rainforest in the US National Forest System, famous for its waterfalls and lush greenery.