Propagating Trillium ovatum from seed: the experiment begins

Western wake robin (Trillium ovatum) and friends abound along our Santa Cruz trails this year. They bloom from February to June. The flower begins white...
And turns pale to deep pink or deep magenta  over time.
Trillium ovatum is native to Western North America. They can live fifty years or more -- at least its rhizomes can.  The above ground parts die back each year, so it could be tricky remembering where they are located in a garden. In the wild, it grows in forests, and in shade or semi-shade. In a garden it likeska nice moist soil, with good drainage.

This year it seems there's been a bumper bloom of Western wakerobin, also known as Pacific trillium (Trillium ovatum), at least in my county (Santa Cruz CA). Consequently there has been a bumper crop of seed capsules along my local seed collection routes.

So I picked a few. (Not in public parks or protected areas.) Five or six capsules along a two mile stretch -- a quite ethically low percentage of available capsules. 82 seeds!

A ripe Trillium Ovatum seed capsule. 
If I succeed I hope they will take root on the more shady north slope down behind the house, and live a long time and prosper there.

It's a plant that takes a long time to mature.  Here's a quick summary of the life cycle:

Gather seeds in July and sow immediately. Keep watered through summer. Seeds will germinate the following spring - or the one after. (Or possibly not at all!)

After germination, basically it goes like this:
  1. The plant remains in the “cotyledon” stage for one summer. The cotyledon is a narrow leaf around an inch to two inches long. 
  2. Next, the plant spends one or more summers in the “one-leaf” stage. This is a "true leaf" not a "seed leaf" (aka cotyledon). It looks like a trillium leaf, only smaller I think.
  3. Then it spends one or more summers in the recognizable three leaf stage. (Trillium - three. Three leaves, bracts, petals, seed chambers, etc.)
  4. Then - finally! it flowers. Generally seven years after germination.
But the tricky Trillium can also revert some years, to any earlier stage except the cotyledon stage. Sounds like a snakes and ladders board game!

If you are still curious about lifecycle - click through to the post Trillium, the Princess of the Forest, volunteer nature guide and retired research forester Bruce Rottink. It which has a great section on the Life Cycle of a Trillium which I summarized above. (BTW the blog, Tryon Naturalist Notes, is written by folks at Tryon Creek State Natural Area in Portland, Oregon. This park even have a Trillium festival!)

For more of Bruce's posts on Trillium ovatum, click here. For example, here's what he says about what pollinates Trillium:
[P]ollinators included several species of beetles, honey bees, bumble bees, crab spiders and geometrid moths. Since the trillium doesn’t produce nectar, at least some of these creatures are here to eat the pollen, and they spread the pollen as an unintended side effect.

Seed Preparation

On to the propagation effort and a lovely discovery I made as I was preparing the seeds. It's not a new discovery, just new to me, complete with all phases: a mystery, a hypothesis, and a confirmation! Such a satisfying experience. Aaah!


How neatly seeds are packaged!

Like a little football!


Open them up and you get... Oh wait - what are those yellow blobby bits on the seeds? 



See them? They are elaiosomes! Food packages for ants - and harvestmen.
The hungry bugs take the seeds away to eat the nice fatty package, and discard the seeds.
Sometimes deer eat them too. I wonder if the seeds survive in their poop? 

This kind of plant dispersal by ants is called myrmechory. (I love words!) Wild ginger also has elaiosomes and so do quite a lot of other plants. Oh, and here is a nice post on the Nature Niche blog about the Trillium ovatum eliaosome, with nice photos.

I wondered how the seed capsules and their seeds get to the ants. I found out the answer today when I was walking in De Laveaga park, a local county park a few miles from my home.

A nice matrix of woodlant plants in De Laveaga Park, including California harebell flowers in the middle.
And a very ripe trillium ovatum in lower left.
I touched that very ripe seed capsule in the lower left of the photo, and it fell right off its pedicel. So I think that's as much energy as the plant puts into dispersal - lets them fall and the ants do the rest. I'm pretty sure also that bugs climb up and get into the seeds in the capsule - but maybe those are not the kind that help the plant propagate itself.

Propagation Protocol

So - how to propagate these seeds? I found an article called Propagation Protocol for Western Trilliums by Sheila M. Klest in Native Plant Journal, Spring 2002.

I also referred to this protocol from Washington.edu. It references Klest's document and others too.

Klest advises collecting in early to late July and sowing immediately. Viability decreases the longer you wait to sow them. They like to be moist, I guess. Good news for seed gatherers: Klest had good results even with slightly under-ripe seed capsules.

Seed Sowing:
Klest sowed either into a pot containing an adult plant, or into a 72-cell plug tray. Here's another nugget of information: "Interestingly, T. ovatum seeds planted into pots containing mature plants always germinate and produce cotyledons the spring following planting."

Not having any potted adult plants (something hopefully I'll have in seven years!), I sowed the seeds into 2-inch liners (little square pots), which are easier to manage than plug trays. One seed per pot. (Klest didn't specify how many per pot, but this way I can keep track of germination rates.)

She did say that there's no difference if you remove or leave the eliaosome on. So I left it on. I'm lazy.

For planting medium she specifies this mix -- 1:1 sphagnum peat moss and perlite. Hm. I have a little bit of peat left and I also recently bought coir.  I'm no longer buying peat as it is not a sustainable product. Or there is anyway a discussion about that. The peat makers say "Oh yes it is!"

I've found that coir, made from coconut husks, is much easier to hydrate than peat. And it has a pleasant texture that is less "clumpy" than peat. It is I think sustainable, though there is a transportation cost associated with it. And some other differences. Coir has a pretty neutral PH value - 6 to 6.7 (according to this article). Sphagnum peat is acidic and so is the soil around my place - mixed evergreen forest and redwood forest. So I sowed about a third in a coir mix as an experiment, and the rest in a peat mix.

Another site specified a planting mix of well-drained soil with leaf mold, peat moss, and decayed material.

Klest also said to sow uncovered. Uncovered? But these are large seeds and need to not dry out. I looked around till I found another site that told me what I wanted to read: that I could cover the seeds!! One site said by same depth as size of seed and another one said about 1/4 inch. Another one said 1/2 inch! Yikes!

So I covered most of them a little - and left a few rows uncovered as a test. On second thought, maybe I'll go back and give some of my seeds thicker blankets!

So we shall see. Really such a small experiment won't give valid data, even if I am very good at following all the instructions but still I'm curious about these variables - coir or peat, covered or uncovered.

CARE BEFORE GERMINATION OCCURS
Seeds sown in summer will germinate the following spring. Or the spring after that.
Water daily! Keep moist - but beware damping off after germination.

Klest specifies covering the pots (or plugs) with 80% shade cloth and keeping them in a greenhouse till fall, and then moving them to a shade house. But I'm keeping mine in my shade house right off. I don't live in Oregon and my greenhouse gets way too hot for these guys, I'm pretty sure.

I prepared 24 pots with coir and perlite and covered the seeds.


I prepared 56 pots with peat moss and perlite and left three rows uncovered. As an experiment.

CARE DURING THE FIRST YEAR (OR TWO) AFTER GERMINATION
Starting in late winter or early spring after sowing (whether cotyledon has appeared or not), give two applications of fertilizer during the active growing period.

The fertilizer specs are: 2 applications of Peters Professional PeatLite fertilizer (15N:16P2O5:17K2O at about 180 ppm N (0.5 tbsp/gal).

She doesn't specify when to do these applications. I think I'll do one application in February and another in May. Unless I learn otherwise. I'm not sure I can find a fertilizer with these specs in less than a 25 lb bag. I'll look around.

CARE AFTER THE FIRST TRUE LEAF APPEARS
Klest says: "After true leaves emerge (second or third spring after planting), plants are watered with the same fertilizer and rate once every 2 or 3 wk." I assume this means during the active growing season - late winter to mid summer or so. And I assume it means during the one-true-leaf phase. (See above for lifecycle summary.)

Below I just pasted Klest's instructions for the far-off time when the three leaves will grow! When I get to that point, if I do, I'll adapt them for local conditions and available materials. Here you go:

CULTURE
The third or fourth spring after summer sowing, trilliums are potted into 3.7-l (1-gal) containers filled with Rexius potting mix (a proprietary mixture of aged fine fir bark, compost, pumice, balanced fertilizer; pH 6.2 to 6.5; Rexius, Eugene, Oregon).

Containers are top dressed with Apex controlled release fertilizer (19N:8P2O5:12K2O; 10 to 12 mo release rate at 15.5 ˚C [60 ˚F]; Simplot Turf and Horticulture, Lathrup, California) once each spring.
Plants overwinter outside covered with Reemay fabric (Reemay Inc, Old Hickory, Tennessee) and white plastic.

Blooms are to be expected in seven years. Whew! I hope in seven years I'll have a post about how amazingly successful my efforts have been. And not about all my unfortunate learning experiences!

Postscript: I am also trying a similar approach with Maianthemum racemosum, western Solomon's seal - trying to support it through its natural life-cycle, in my shade house. No end of fun!

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