Before
we begin to think about how
to grow California native plants, 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 mean 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 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 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
Mediteranean 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!
In the wild, seed dormancy is usually overcome by the seed spending time in the ground through a winter period and having its hard seed coat softened up by frost and weathering action. By doing so the seed is undergoing a natural form of "stratification" or pretreatment. This cold, moist period triggers the seed's embryo, its growth and subsequent expansion eventually break through the softened seed coat in its search for sun and nutrients.
Meeting
some of these conditions, for most gardeners can be a tad difficult.
In order to imitate conditions that would ameliorate these
inhibitors, one must understand the process the seed goes through in
real life in order to mimic it.
Being
essentially wild plants, these plants 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
can create wacky germination of their seeds that drive gardeners
batty but can be imitated, 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
In
most plants of the world, the process of stratification is to
simulate cold winter conditions which most wild plants have
mechanisms to prevent premature sprouting that would have small
plants killed by cold while they are still very tender.
Stratification
is the process of subjecting seeds to both cold and moist conditions.
Typically, temperatures must be between 34°F and 41°F. The term can
be traced to at least 1664 in Sylva, or A Discourse of
Forest-Trees and the Propagation of Timber, Vol. II. where seeds were
layered (stratified) between layers of moist soil and exposing these
strata to winter conditions. Thus, stratification became the process
by which seeds were artificially exposed to cold-moist conditions
between layers of soil or peat to encourage subsequent germination in
spring. Seed of many trees, shrubs and perennials require these
conditions before germination will ensue.
In its
most basic form, when the stratification process is controlled, the
pretreatment amounts to nothing more than subjecting the seeds to
storage in a cool (ideally +34° to +36°F; just above freezing) and
moist environment for a period found to be sufficient for the species
in question. This period of time may vary from one to three months.
To
accomplish this you merely place the seeds in a sealed plastic bag
with moistened vermiculite
sand
or
even a moistened paper towel
and
refrigerate it. Use three times the amount of vermiculite as
seeds. It is important to only slightly dampen the vermiculite, as
excessive moisture can cause the seeds to grow moldy in the
bag.
The medium must be sterile and must be appropriate to the seed's habitat. We would probably find vermiculite or sand to be most appropriate while peat will not be as appropriate for CA natives.
The medium must be sterile and must be appropriate to the seed's habitat. We would probably find vermiculite or sand to be most appropriate while peat will not be as appropriate for CA natives.
After
undergoing the recommended period of stratification, the seeds are
ready to be removed and sown in the nursery bed for germination.
Alternatively, the seed may be sown in small pots filled with moist
soil and then the whole thing enclosed inside a plastic bag before
placing inside a common refrigerator.
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
via the initial watering and that might 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 primarily of Coast Live
Oak (Quercus agrifolia)
leaves. When I want to start Matilija Poppy from seed, I cover them
with dry Live Oak leaves, combined with few dried pine needles, 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 that is a predominant species in the Matilija
Poppy's habitat. I might be just a little too fixed on this, but my
poppy germination has been excellent. Remember, should you do this,
you must not use a plastic container!
