Frosted Fern

I was asked a question on my miniature ferns for fairy garden post about one of the plants included in the photo of Hirt’s Gardens fern assortment. Keep in mind, I am in no way associated with them other than as an admirer of the lovely plants they sell online.

The plant in question is in the bottom left-hand corner of the photo. It is a beautiful looking plant for sure. I’ve seen them in grocery stores around Christmas-time. They were so soft and delicate-looking that I saw quite a few folks touching them as if to confirm they were a live plant. But, at the time, the budget just wasn’t there to spend $10 plus tax for what amounted to a mystery plant. Looking back, it wasn’t a bad price for the size of the plant. Maybe this Christmas I’ll treat myself to one if the stores carry them again.

So what are they anyway?

First the disclaimer, I’m going by a photo and hope it’s a match. If not, I’m awfully close. That out of the way, let’s get to it.

Let’s start with the name everyone seems to agree on – Selaginella kraussiana. Where things start to get less clear is the other names they are known by – frosty fern club moss, arborvitae fern, spike moss, frosted fern, Krauss’s spike moss, ground pine and probably a few more I’ve left out. But, is it a fern or a moss?

The pretty specimen shown here is from the Hawaiian biologists Forest & Kim Starr.

Well, the correct answer is neither. It’s sorta both. Club mosses are fern “allies.” They are a perennial evergreen with small, lacy leaves. And they have shallow roots. That pair of characteristics means they’re not a moss. But, are they ferns then? Well, not really.

They do grow from spores like ferns do. Both are non-seed vascular plants. And, both have stems with vascular systems. Fern allies, however, have smaller leaves with a single mid-vein. And, their spores form on a different part of the plant.

Science aside, the main question most tiny green gardeners want to know – How does one maintain frosted ferns?

Caring for Frosted Ferns

First off, let me be clear, I have not owned one of these plants and my information is only second and third hand.

This is truly a tropical plant – it likes it warm, it likes a fair amount of light, and it likes it moist and humid. But, it is not a happy camper if you give it a lot of direct sun. A frosted fern would seem the perfect plant for terrariums then. Being such a fan of warmth and humidity, it does seem odd that it would be primarily available in the colder months.

When kept indoors, frosty fern likes bright, indirect light. Anything lower than 50 degrees Fahrenheit and it will probably die. It’s also not a fan of temperatures above 80. 60-70 is the sweet spot.

I’ve seen a number of recommendations on caring for frosty fern plants and at least one of them appears to have gotten it extremely wrong. They recommend not watering until the surface of the soil is slightly dry. Virtually every other source says to never let the soil dry out and always keep it moist.

My suggestion would be if you keep your frosty fern indoors, but not in a terrarium, that you should give it a little drink every day and a long drink once a week until the water begins draining out the bottom of the pot. That’s what I’ve been doing with my ferns in 2-inch pots. Miss a day and they will pout. Miss 2 and you might be in trouble.

As I’ve said, I’ve not tried one of these, yet. Though, I do wonder about them being variegated. With the ferns we’ve tried, the variegated ones were the hardest to care for and sadly the first to die off when temperature and water conditions weren’t to their liking.

Where to buy frosted ferns?

Where to buy frosted fern? As I said, the original picture that led to Jami posing her question is for the fern assortment sold on Amazon. The seller clearly states that the photo may or may not represent the plants that you’ll actually receive. You could buy the assortment and hope you receive a frosty fern or Krauss’s spike moss. Or, you could simply buy one of these pretty frosted fern plants from Hirt’s and JM Bamboo.