Guest author Dan Songster contributed this article about the California Polypody Fern as the featured California native plant for January. Happy New Year!

• What: California Polypody Fern (Polypodium californicum)
• Type: Creeping perennial, summer deciduous
• Light: Light to fairly heavy shade
• Soil: Good draining but can take heavy soils too
• Water: Does best with some winter and spring water 

As the weather cools, days shorten, and moisture (either the hoped for rain, or from your hose) is added to your garden, the small but lovely California polypody fern re-emerges from its summer slumber to imbue your garden with a most lovely green found in nature–a green that speaks of freshness and life.

Many years ago, I remember asking experts about their favorite colors in the native garden: the blue of ceanothus, the red of monkey flowers, the soft purple of the lupine? Carol Bornstein surprised me by strongly stating her favorite garden color was the lovely fresh spring green of the California polypody fern.

Where It Grows in Nature

This is a creeping perennial fern that grows in moist rock crevices as well as most California soils. Polypodiums just need wet feet in winter and early spring, as the ground dries out, so do they, gradually going dormant in mid-summer. This fern is almost always associated with seeps in the coastal areas and in the middle Sierras, and grows in part shade, but sometimes can be found thriving and slowly spreading in the fairly deep shade of many of the oaks. With the first coolness of autumn the “fiddleheads” emerge and unfurl. The energetic bright green foliage thrives all winter and into spring. 

Where to Buy This Fern

I apologize for touting a plant that is not readily available even in our California native nurseries. However, I do have good news: Tree of Life Nursery is currently growing a crop of two-gallon plants that should be available this spring. If you can find this fern, it makes a wonderful addition to the shade garden where it is perfectly adapted to our dry summers.

Care

Very little effort is required to care for this fern. It will emerge with the first rains in fall and provide beautiful green foliage through spring. Some people remove the fronds once they have gone completely dormant but that is not needed. It will spread slowly and is easy to manage if it moves out of bounds. After a few years, the plant can be divided by digging out sections of the clump in the fall and replanting in another favorable area in your garden (or sharing with a particularly good friend). 

Further Information

If you would like to learn more about this fern and read a quick summary of the reproductive difference between ferns and seed producing plants, consider this beautiful illustrated article by Dirk Walters of the San Luis Obispo chapter of the California Native Plant Society.

‘Sarah Lyman’

Polypodium ‘Sarah Lyman’ is an interesting variety of the California polypody fern with finely divided leaves. It is a bit more upright, (up to 18 inches tall), and it has a frilly look due to more finely divided leaf margins.

In 1897, Sarah Lyman and her son Jack were walking on a hill in Napa County and came across this interesting fern. She transplanted a clump to her yard. Over the years, it grew and she shared it with friends.

In time, the Napa Chapter of the California Native Plant Society became aware of the plant and worked to ensure that it was protected. At the urging of Jack Lyman, this special form was named for his mother Sarah. Reports indicate that this beautiful fern is still found in the original location where Sarah Lyman found it more than a century ago. And of course, it thrives in our gardens as well.

Updated Information: The fern that is often sold as Polypodium californicum ‘Sarah Lyman’ or Polypodium calirhiza ‘Sarah Lyman’ is actually a hybrid between Polypodium californicum and P. hesperium, both California natives.  This cultivar has all the characteristics of California polypody, but its leaves are ruffled and much showier. It’s a little charmer that’s more often available from California native nurseries and online fern sources than the straight species.