Thursday, February 13, 2014

California Native Plants From Seed

Flowers of Romneya coulteri at The Learning Garden,
grown from seed stratified with fire.
Before we begin to think about how to propagate California native plants from seed, let's think about why we might want to grow California native plants. The native vegetation, through evolution, is adapted to this climate, these soil types and interacts with other natives (insects, mammals, birds, reptiles) in an ecological dance that was going on long before humans arrived, and certainly before the present civilization of humans arrived on scene. Their niche in the ecology of California gain some advantages to the gardener:

They Save Water
Once established, many native plants need little or no irrigation. Not only does one save the limited amount of water we have available, that saves one money.
Lower Maintenance
Less pruning and no fertilizers means less work for a gardener, saving time to learn more propagation and take more courses at UCLA Extension
Pesticide Freedom
Native plants interact with the insects of their environment in a way that eliminates pesticide use. The pests and diseases evolved with the plants and native plants have their own defense against them. Beneficial insects often become collateral victims when we spray pesticides (even more true if we use organic methods). Stop poisoning ourselves and our world.
Invite Wildlife
Native plants, birds, butterflies, beneficial insects, and interesting critters are, as noted above, co-evolved to be here. Current research shows confirms what many have intuited for many years: native wildlife clearly prefers native plants. California’s wealth of insect pollinators can improve fruit set in your garden, while a variety of native insects and birds will keep your landscape free of mosquitoes and plant-eating insects. Open your garden to these wild living things that live among us, despite what we have done to their habitat.
Support Local Ecology
While creating native landscapes can never replace natural habitats lost to development, planting residential and commercial gardens, parks, and roadsides with California natives can provide a “bridge” to nearby remaining wildlands.

California native plants are a world unto their own, mostly because we have so little familiarity with them. By that I mean, our culture's experience with growing these plants is something like 250 years – many a good deal less, like 60 years. And that is also the time we've been selecting them for our gardens. On the other hand, beans, lettuce, cabbage, onions have been in cultivation for hundreds, sometimes thousands, of years. Over that time, civilizations have selected year after year those plants that adapt to our culture, or in the case of stubborn plants, we have figured out how to make that plant grow to suit us. This selection process has yet to occur for California natives. Add to that the fact that these are plants from the driest of the world's Mediterranean climate that have adapted to survive with cool, wet winters and long, hot, droughty summers, in a land ravaged by frequent wildfires and you have plants that are, by nature, not ready to accept the regimen we intend to use to make them grow.

The cycle that California native plants live by is almost perfectly backwards to the cycle by which we want to make them grow. We want to plant in Spring (along with our tomatoes and marigolds) and have flowers blessing our landscape by July, if we insist on this, we will spend much more money on therapy than plants! Plant California natives in fall, when we hope for rain to establish them, and enjoy the fecundity of flowers in March/April. Right now, in the California native garden, some salvias are blooming, I've seen Blue Eyed Grass and some poppies blooming. By mid-March, the scene is breathtaking!

Being essentially wild plants, these plants of our home employ many different mechanisms to ensure that at least some of the seeds will find conditions acceptable to carry on the family name. These mechanisms cause for wacky germination of their seeds that drive gardeners batty and can be imitated by gardeners, if one knows the mechanisms a given plant uses to germinate at the most propitious moment for plant survival include:
  •      germination after a fire
  •      germination after cooler temperatures indicate winter
  •      germination as daylight gets longer, indicating more longer days
  •      germinating over a long period of time to have at least some of them hit ideal growing conditions

Meeting some of these conditions, for a gardener can be difficult. In order to imitate conditions that would break these inhibitors, one must understand the process the seed goes through in order to mimic it. In the case of fire causing germination, is it the heat, the chemical residue left by the fire or both that causes the seed to germinate when there is less competition for natural resources? If it is chemical, the commercially available 'Liquid Smoke' could be added to the container of the initial watering and might be the key to unlock germination. If it is heat, one will need to start a fire over the seeds to get the heat. For example, in germinating Matilija Poppy (Romneya coulteri) the fire that would burn around these seeds in nature, would be composed of Coast Live Oak (Quercus agrifolia) leaves. When I want to start Matilija Poppy from seed, I cover them with Live Oak leaves and set them on fire. My thought is that the temperature, the chemistry needed for the poppy to sprout will best be approximated by those leaves of the oak with which it can often be found. I might be just a little too fixed on this, but my results of poppy germination have been excellent.

Cold and heat is usually coupled with the word 'stratification,' cold stratification being the most common.

Collecting and Drying Local Seed


Make a point of picking only plants growing in prime locations. Individual plants with many insect holes and obvious poor health are probably located at the extremes of their preferred growing conditions and may also have distinctly atypical biochemistries as a response to their compromised growing conditions. Always check around the vicinity after you have located a desired plant. In fact, it should be stated that the best collector has scouted the area weeks ahead of going to collect seed – this needs to be a thoughtful and deliberative process. 

However, there may be times when there isn't any 'wiggle' room – in that case, be cautious, always error on the side of restraint. A thoughtless collector can wreck havoc on an ecosystem. There may be a whole field of your desired plant over the next rise or around the bend in the road. On the other hand, it may be the only one in the whole valley – and should be absolutely left alone. Furthermore, a plant common in one state may be a rare, protected plant in the next state, so check with a local California Native Plant Chapter first if in doubt.

Certain conservation practices are always necessary. The following figures should be your guide only.  We all know seed collectors that have paper bags in a spare room filled with seed from ten years or more ago that have never been germinated (and at this point are probably dead) so once more, error on the side of caution.  If a plant grows in large stands, never take more than a third of the plants' seed. If it is a large, solitary bush or tree, never pick more than a fourth of the seed. If it is a large stand of perennials that is healthy, you can be more relaxed with the material as they have more than one year to produce more seed.

Wherever you gather, presume that you will come back the next year to the same place and find the plants still healthy. Don’t make a common mistake of looking many days for a plant, finding it at last, and taking a whole load of its seed back with you – it’s like you are punishing the plant (indeed the species!) for your frustration. And most of it, mark my words, will go to waste.

Remember, know a few plants well, know what you will need and don’t try for the record amount of seeds never planted (and in a year, designated 'uncertain germination percentage').


Dry your seeds promptly upon return. Lay the seed on screens away from direct sunlight in a dry place and, above all, away from rodents and insects. Fear of insects and rodents have spurred me to use my food dryer to do the job as quickly as possible. Dry your seed as promptly as possible and, once dry, place in paper envelopes or in glass jars. Make sure your seed stock is insect free before storing. It can be terribly disconcerting to find your stored seed has become insect larvae feed and you have nothing to show for your work.