germinating seeds
At first glance, a seed appears to be just a small,
simple little thing, but hidden inside is
pure potential—the potential to grow
into a beautiful, mature plant that can
host beautiful flowers and delicious
fruits. Many of the foods we eat
to survive and the medicines we
take to stay healthy come from
plants that got their humble
starts as seeds. Inside that
simple-looking seed exists all
of the genetic information
needed for that plant to grow
throughout its entire life cycle.
Whether a certain plant is
destined to create fruits, grains
or maybe just oxygen, its destiny
is retained inside that little seed.
Once a seed germinates, sprouts and
begins to grow, nature kicks into gear
and life-sustaining processes within the
plant begin. But for a seed to begin its life as a
growing plant it will require a little help.
The seeds of flowering plants (angiosperms) are placed into
two distinctive categories: monocotyledons (monocots) and
dicotyledons (dicots). This classification is based on one specific characteristic of a seedling. Cotyledons are the first leaves
that an infant plant will grow and they will act as a food source
for the seedling until the emergence of the first true leaves,
when the plant begins the process of photosynthesis to provide
itself with carbohydrates for energy. Monocots are classified as
such because they only have one cotyledon (seed leaf) while
dicots have two. Plant seeds classified as monocots include
wheat, corn, sugar cane and bamboo. Seeds classified as dicots
include beans, tomatoes, peppers and cucumbers.
A seed is essentially made up of three parts: the seed
embryo, which is basically a baby plant that will grow and
mature under favorable conditions, the endosperm that will
supply the initial food and energy source for the growing
embryo, and the seed coat—the hard outer shell that protects the seed until it is ready to grow.
Germination is
the process in
which a seed
and its embryo
go from a dormant state to
an active, growing
state. Successful seed
germination is dependent on
certain conditions being met.
These conditions are both
internal and external and
can vary from seed to seed.
The external conditions that
are most crucial are water, temperature, oxygen and, with certain seeds, even light or darkness.
Water is essential because a mature
seed is often quite dry. Seeds take in
water through a process called imbibition. As water accumulates in the seed, it
causes the seed coat to swell and break apart.
Water also activates the breaking down of the endosperm, chemically converting it into a useable food source.
Temperature has an effect on the metabolism and growth rate
of cells within the seed’s embryo. Seeds usually have a temperature range in which they will germinate and germination
won’t likely occur above or below this range. For most seeds,
this range is between 60 and 80°F, but some can germinate in
soil temperatures as low as 40°F. Oxygen is required for proper
seed germination. In gas form, oxygen will reside in soil pore
spaces and assist in the development of a much-needed root
system. If the seed is planted too deep or if the soil becomes
too waterlogged, the seed may not germinate.
When germinating seeds at home or in a greenhouse the first
thing to think about is whether or not a certain seed should
be started and transplanted to another location or if it should
be directly sown into its permanent home, whether that is in
soil or some other growing medium. Plants like radishes and
carrots should not be started indoors and transplanted at a
later date, as this may result in disrupted growth that can lead
to unfavorable results. However, starting tomatoes, peppers
and cucumber seeds, just to name a few, indoors is a great
way to get an early jump on the outdoor growing season or
for an indoor garden. When choosing a medium to germinate the seeds, look for one that includes words such as
seed starting mix. This type of growing medium will likely
have a moderate elemental fertilizer charge that will benefit
newly sprouted seedlings. Seeds can be germinated in many
different styles of trays and containers, so choose the type
that best fits the project at hand. If starting just a few seeds,
a simple, flat starting tray will work. When planting many
seeds at once, it may be wise to use trays that are divided into
separate growing chambers to cut down on the amount of
transplanting needed as the plants grow. Remember, most
seeds will germinate at average room temperature, but some
Many of
the foods we eat to
survive and the medicines
we take to stay healthy
come from plants that
got their humble starts
as seeds.”
Starting tomatoes, peppers and cucumber seeds indoors is a
great way to get an early jump on the outdoor growing season
or for an indoor garden.
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Maximum Yield USA | February 2014