There is a 37 acre Botanic Garden in Encinitas, not too far from Carlsbad. The Garden has plants from around the world, and specializes in plants from semi-arid climates.
Along the coast of California are wetlands where marshgrass and birds and fish are born and grow in very robust ecosystems. Along the many coastal towns that make up North County San Diego are lagoons that separate those towns, and give nature a chance to grow, and tides to flow to and from the ocean keeping the lagoons fresh and an active part of the ecology. Carlsbad has the Batiquito lagoon, which has been treated poorly and then better in the 20th and 21st century. It seems to be a treasured part of the town now, with many large houses having views that overlook the nature that it provides, and an active nature trail around it, where may people were touring and talking about nature. It’s a nice place to walk and watch birds, and one of the images I captured on my trip down the trail next to the Lagoon was a rat nest. I’m looking forward to seeing what the lagoon looks like in other seasons.