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Sowing Your Seeds

Starting seeds can be a very rewarding activity and even trying to germinate some of the more challenging seeds can be done if you
find out which techniques should be used.

If certain basic conditions are met, most annual and
vegetable seeds do not require special treatment to achieve
good germination. Some seed takes longer to
germinate than others. If sowing times seem wide, remember
that many factors will affect the growth of the plants and desired
planting dates will vary based on your area. To get a more exact
sowing date, first find your frost-free date, which is the
approximate date of your area’s last spring frost. Then back up
the number of weeks required to grow the transplants to get the
sowing date.

Different seeds have various needs in order to germinate. Some seeds need light (press seed on top of the soil) or darkness (generally plant to the depth of
the seed size) for optimum germination.

There are a number of varieties that are more difficult to
germinate than others. These seeds will often have poor or
even no germination unless a strict regimen is followed. Very
small seeds such as petunia are often available pelleted.

This process coats each seed to make it for the consumer
easier to handle and germinate faster. The extra cost is
definitely worth it. Small seed that is not pelleted needs to be
carefully tapped from the packet and gently pressed into the
soil.

Seeds with a hard seed coat need to be nicked or soaked to achieve
good germination. This is done in 2 different ways. Smaller
seed can be soaked in water 24 hours before sowing to soften
the seed coat to allow for germination. Larger seeds need their
coating gently scratched without harming the interior parts. This
is known as scarification. While in natural conditions this coat
would eventually be broken down, the impatient gardener can
speed the process by using a knife or file to make a shallow cut.
This allows moisture to enter and the seed to germinate.

There are some varieties, particularly perennials that need to
be put into the refrigerator prior to sowing to break dormancy.
This process is called stratification where by the seeds are
tricked into thinking they are experiencing winter. It isn’t really
necessary for the seed to spend the cold months in the ground,
as long as it thinks it did. This can easily be done by placing
the seeds in a small container with moist (not wet) sand,
peat or vermiculite, and leaving in a refrigerator for four to
six weeks.

Not all plants can be started indoors; some don’t like to be
transplanted at all and their seeds must be sown directly
into the garden.

You can use just about any container to start seeds as long as it
is at least 3″ deep to allow for the roots to grow.

You can use Yogurt cups, plastic take-out containers or margarine tubs.
You can save any cell packs and trays you get from the nursery. All
containers should have holes in the bottom for drainage. It
is wise to disinfect all containers with a mild bleach
solution. You will also need a rimmed tray to set your
containers in.

For simplicity, you can use peat pellets, which
are a growing container and planting medium in one.
When soaked in water, the pellets grow to seven times their
size. These pellets can be planted directly in the garden
when the seedlings are ready.

It is best not to use the soil from your garden.
Not only is it too heavy and provides poor
drainage, you can run the risk of bringing in weeds and garden
soil may host some disease organisms detrimental to your
seedlings. There was a time that gardeners sterilized their
garden soil in the oven to use for their seeding, but that is a
very tedious and smelly chore. It is best to use a
commercially prepared soil-less mix, which can be found
almost everywhere. These mixes usually contain sterilized
peat moss, vermiculite and perlite. They are light in texture
and retain large quantities of moisture while still being well
drained.

The general rule for seed starting is to start seeds warm and
grow seedlings cool. Don’t try to germinate your seeds on the windowsill.
The outdoor temperatures will make this area too cool. Most seeds are
genetically programmed to germinate only in warm soil.
You can keep the seed trays consistently warm by placing
them on top of a water heater or refrigerator. Fluorescent
lighting also can keep the soil warm. If your area is quite
cool, a seedling heat mat may be your best option.
Seeds need to be constantly moist in order to
germinate. Do not let the growing mixture dry out or get too
wet. Moisten the growing mix thoroughly before sowing. Stir
the mixture with your hands to distribute the moisture. After
the seeds are sown, place a humidity dome or plastic wrap over
your container to slow evaporation. Check every day for signs
of germination and remove the cover as soon as you see a
sprout so that the air can circulate around the emerging
seedlings. Water with a fine spray of warm water or from the
bottom.

Lack of light is probably the number one reason
people get discouraged. Seedlings need 14 - 16 hours of light
from the moment they germinate. They also need at least 8
hours of darkness to process their food and grow. Growing
seedlings on a windowsill is not recommended, as they will
stretch toward the light. If the windowsill is your only option,
turn the containers daily so they don’t have to stretch and reach
for the light. You will know if your seedlings need more light if
they are pale and weak.

Fluorescent lighting or grow lights are your best option. Even if
you don’t have a store-bought stand, one can be made with a
cast-off fixture, some cedar or treated lumber, screws, nails and
cords. The best growth will occur under the maximum light you
can provide. Mix the types of bulbs used since the cool white
provides light in the blue/green range and encourages leaf
growth, while a grow light or warm light provides light in the red
range which encourages flowering. This way you have a full
spectrum of light. Replace the bulbs yearly, as the light intensity
decreases significantly even in the first few months of use.
Keeping bulbs longer doesn’t save money compared to the
poorer growth of the plants. Get your plants as close to the
light as possible by putting the lights on adjustable chains
keeping them 2 - 4 inches above the tops of seedlings. Move
the light fixtures up as the seedlings grow.

The new seedlings need additional space to
grow as soon as their first “true” leaves appear. It may seem
heartless, but the weakest and spindliest seedlings need to be
cut off at soil level so that the strongest ones can get stronger.
If your seeding is rather dense, do not pull out unwanted
seedlings as their roots may be tangled up and damage the root
of the seedling remaining.

At this point it is a good idea to place a fan around your plants.
This will make their stems sturdier and get them prepared for
for the outdoors. As well, good air circulation will keep
moulds and mildews at bay.
If you did your planting in individual containers, transplanting may not
be necessary before you set them outside.
Seedlings in seed flats need to be transplanted
into 4″ containers by the time you have 4 true leaves. This
will give your seedlings more room to grow, stimulate the
feeder roots and improve ventilation. To transplant, hold
the seedling by its’ leaves, not the delicate stem. With a
butter knife, spoon or fork, gently cut around the seedling
root and lift up. Place into a pre-moistened container,
slightly deeper than they were in their flats. Firm soil
around the seedlings, water immediately.
After transplanting, fertilize once a week
with transplant fertilizer or a half-strength well balanced
fertilizer. After about 3 weeks you can start fertilizing at full
strength. Over-fertilization can result in leggy seedlings. If
your seedlings are starting to look leggy, pinch back the
growing tips to promote more branching. This can be
repeated every week or so to promote compact, bushy
plants.

Hardening off is basically getting your young plants ready for their new
Home, the great outdoors.
There are many different ways this can be accomplished. At least
a week before you plan to set the plants into the ground
they need to gradually get used to the sun, wind and
various outdoor temperatures. A cold frame, which is a
sheltered unheated box with a translucent cover is the best
means for this transitional period. The lid can be gradually
raised to expose the plants to more sunlight.
These unprotected plants will have to
be brought back indoors each night unless you know it is
going to stay above 50°F/10°C all night long.

If you have followed the directions above, your seed starting should be
relatively trouble free. There are however, a couple of
problems that may creep up on you. INSECTS: spray
insecticidal soap on spider mites, aphids or whiteflies as
soon as they appear. DISEASE: Using clean containers and
soil-less mixtures should keep diseases at bay. A common
disease is Dampening Off, which is a fungus that attacks the
plant at the soil line. With all this is mind, your experience should
be fun and rewarding.

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