How can soil compaction be effectively managed in gardens?

Using a soil aerator is an effective method for managing soil compaction in gardens. Soil compaction occurs when soil particles are pressed together, reducing pore space and leading to poor water infiltration, root growth, and soil aeration. A soil aerator creates holes in the soil, which helps to relieve compaction and improves air and water movement within the soil. This process allows roots to access more oxygen and nutrients, promoting healthier plant growth.

To elaborate on the other choices: regularly irrigating does increase moisture, but it does not address the physical density of compacted soil. Adding more mulch can help with moisture retention and temperature regulation, but it does not alleviate existing compaction problems. Reducing plant diversity could actually lead to less resilience in a garden ecosystem and does not provide any benefits towards managing compaction.