Moss magic

In my opinion, no coastal Pacific NW garden is complete without moss softening the edges of a rock garden or nestling between paving stones. Now that the rains have returned, mosses are lush green sponges, absorbing sound as well as water. They are the finishing touches to our native landscapes.

A few months ago, however, mosses looked quite different. With our particularly hot and droughty summer, mosses were brown, dry and brittle just like our lawns. But unlike those dead blades of grass, the mosses were only in a state of environmental dormancy. All it took to revive them was water.

Here’s a patch of moss in our home landscape during a hot dry spell. It’s dry and brown:

Here’s the same patch of moss 20 minutes after I watered it:

How can mosses recover so quickly? Well, mosses are one of the most primitive groups of land plants still in existence. They lack a true vascular system, so their “roots” are only anchoring structures – they don’t absorb water. Instead, water and nutrients are taken up over the leaf surface. As soon as water hits the leaves, it’s absorbed and literally throws the switch to turn everything back on. Leaves expand, chloroplasts start to absorb sunlight, and the photosynthetic machine is humming along.

In fact, my undergraduate major advisor was a bryologist (one who studies mosses). Jack Lyford’s lab was stacked ceiling-high with shoe boxes. Each box contained a different species of moss – completely dried out of course. All he had to do was take out a piece and place it in a dish of water. Within minutes it was fully functional and ready for study.

So make room for some moss in your garden. It’s a tough and fascinating little survivor.