Over the years I've observed in my garden that the different life vitality levels correspond to what is happening at each stage of the garden cycle. The fall equinox activates the new year's cycle. The environment in which the new cycle is "born" (the garden) is quiet and at peace. The general garden feels "relaxed." The lower life vitality level with its lower activity creates the perfect environment for the birth of the new cycle.

— Machaelle Wright, The Perelandra Garden Workbook

The Equinox and Solstice Cycle explained:

This is for anyone who cares about nature's role in our lives and on our planet. Gardeners, soil-less gardeners and non-gardeners will all benefit from acknowledging this change of season, the start of a new cycle. The planet will benefit too.

This excerpt, from The Perelandra Garden Workbook by Machaelle Wright, explains the importance of the solstice and equinox times and why we should all take a moment to recognise and participate in the start of the new season and celebrate with nature in those special moments.
– The Solstice and Equinox Cycle (5 mb PDF)

As Machaelle explains:

"The release of life vitality that triggers each stage of the equinox/solstice cycle happens with or without human awareness or attention. It’s part of earth’s natural rhythms. But we co-creative gardeners can choose to actively participate with nature at these special times. Nature once said to me that nature is powerful beyond belief and humans are powerful beyond belief. But when nature and humans act together, that combined power is intensified a hundredfold. . . . This is another one of those times where a small gesture on our part can do a lot for the moment."