PROPAGATING PLANTS FROM SEED

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PLANT PROPAGATION
ASEXUAL PROPAGATION
- VEGETATIVE, CLONES
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CUTTINGS
STEM
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LAYERING
TIP
SIMPLE AN COMPOUND
MOUND
AIR LAYERING
DIVISION AND SEPARATION
STOLENS AND RUNNERS
OFFSETS
BULBS AND CORMS
CROWN DIVISIONS
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GRAFTING AND BUDDING
TISSUE CULTURE
TIP
MEDIAL
CANE
SINGLE EYE
DOUBLE EYE
HEEL
LEAF
WHOLE LEAF WITH PETIOLE
WHOLE LEAF WITHOUT PETIOLE
SPLIT VEIN
LEAF SECTIONS
ROOT
SEXUAL PROPAGATION – EXCHANGE OF GENETIC MATERIAL – SEEDS, SPORES – RECOMBINATION,
DIFFERENT
ASEXUAL PROPAGATION
Asexual propagation does not involve exchange of genetic
material, so it almost always produces plants that are identical to
a single parent
Advantages
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The offsprings are genetically identical and therefore advantageous traits can be preserved.
Only one parent is required which eliminates the need for special mechanisms such as pollination, etc.
It is faster. Organisms multiply quickly . .
Many plants are able to tide over unfavorable conditions. This is because of the presence of organs of asexual
reproduction like the tubers, corm, bulbs, etc.
Vegetative propagation is especially beneficial to the agriculturists and horticulturists. They can raise crops like
bananas, sugarcane, potato, etc that do not produce viable seeds. The seedless varieties of fruits are also a result
of vegetative propagation.
Tissue culture is used to grow virus-free plants.
Disadvantages
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The plants gradually lose their vigor as there is no genetic variation. They are more prone to diseases that are
specific to the species. This can result in the destruction of an entire crop.
Since many plants are produced, it results in overcrowding and lack of nutrients
STEM CUTTINGS
TIP
SINGLE EYE
MEDIAL
DOUBLE EYE
CANE
HEEL
LEAF CUTTINGS
WHOLE LEAF
W/ PETIOLE W/O PETIOLE
SPLIT VEIN
LEAF SECTIONS
ROOT CUTTINGS
LAYERING
TIP
SIMPLE
MOUND
COMPOUND
AIR LAYERING
DIVISION AND SEPARATION
STOLENS & RUNNERS
0FFSETS
BULBS
CROWN DIVISION
CORMS
TISSUE CULTURE
This asexual method consists of asceptically growing plant tissue
such as cells, meristems, shoot tips, embryos, ovides, root or
stem and leaf sections in a laboratory vessel containing a
microbe-free nutrient medium under controlled environmental
conditions. Can be used to propagate various species of plants,
both easy (African violets, coleus, chrysanthemums) and difficult
(orchids, ferns, weeping figs) to propagate
GRAFTING AND BUDDING
Grafting and budding are methods of asexual plant propagation
that join plant parts so they will grow as one plant. These
techniques are used to propagate cultivars that will not root well
as cuttings or whose own root systems are inadequate. One or
more new cultivars can be added to existing fruit and nut trees
by grafting or budding.
SEXUAL PROPAGATION
• Sexual propagation involves the union of
the pollen (male) with the egg (female) to
produce a seed. The seed is made up of
three main parts: the outer seed coat,
which protects the seed; a food reserve
(e.g., the endosperm); and the embryo,
which is the young plant itself. When a
seed is mature and put in a favorable
environment, it will germinate, or begin
active growth.
ENVIRONMENTAL FACTORS
THAT AFFECT GERMINATION
MOISTURE
HEAT
OXYGEN
LIGHT
SEED ANATOMY
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1. 2cotyledons
2. microphyle (hole)
3. hilium (scar)
4. seed coat
6. plumule
7. radicle
WHAT SEEDS NEED TO GROW
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SOIL
MUST USE SEED STARTING MIX WITHOUT
FERTILIZER NOT PLAIN GARDEN SOIL
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TEMPERATURE
SEEDS GERMINATE BETTER IF THEIR SOIL
(NOT AIR, SOIL) IS CONSTANTLY 70O OR
ABOVE. (SOME 80O TO 85O)
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MOISTURE
SEEDS NEED TO BE KEPT CONSTANTLY
MOIST BUT NOT TOO WET
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LIGHT
MOST SEEDS DO NOT NEED LIGHT TO
GERMINATE BUT THE MOMENT THE SEED
HAS GERMINATED LIGHT IS NECESSARY
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OXYGEN
RESPIRATION TAKES PLACE IN ALL
VIABLE SEED. THE RESPIRATION RATE IN
DORMANT SEED IS LOW, BUT SOME
OXYGEN IS REQUIRED. THE
RESPIRATION RATE INCREASES DURING
GERMINATION.
SEED GERMINATION
SOWING YOUR SEEDS
• MATERIALS:
CONTAINERS: Either purchased pots or flats or containers
you've saved. Used pots should be cleaned and disinfected by
soaking in 1 part bleach to 10 parts water
• SOIL: Seeds do best in a
soilless mix where there are fewer
inherent problems than with garden soil
• PLANT LABELS: To remember what's what
• INDELIBLE INK PEN, PENCIL, OR MARKER
• STIFF CLEAR PLASTIC OR PLASTIC BAGS: Will
trap warmth and humidity where the seeds need it
• WATER: Use tepid water for seeding and until seedlings develop
true leaves
• LIGHT:
light
Will need some kind of florescent or high density plant
Seed Starting Materials
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Seed
Starting
Materials
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1. The Seedmaster, a rotating wheel seeder for dispersing
small seed as you rotate the wheel (the yellow pieces are
click-in filters for different seed sizes)
2. plastic plant labels
3. a dibbler or dibber for poking little holes in soil
4. a fine-point black waterproof marker (Sharpie) for
labeling
5. the mini-transplanter is essentially a tiny, stainless steel
shoehorn for easy liberation of plugs from their cells
6. a moisture meter to stick in the soil
7. plant snips for thinning seedlings
8. Mini-Sim seeder: fill and shake out
9. suction seeder with three tip sizes: squeeze the bulb, put
the tip on a seed, release to hold, squeeze again to drop
10. digital timer for keeping track of repetitive tasks like
bottom-watering trays one by one
11. plant light meter, reads in footcandles, with settings for
indoor and out
12. digital indoor/outdoor min/max thermometer/hygrometer,
mainly for keeping track of temperature
13. magnifying glass with light, for examining seedlings up
close
14. soil scoop for filling plug sheets and pots with seedling
mix
15. spray bottle with good quality spray head (more water
per pull)
16. small plastic flats
17. small bulldog clips
STARTING YOUR SEEDS
• PREPARE A SEED STARTING WORKSHEET
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TYPE OF SEED (SPECIES, CULTIVAR)
SOURCE (SEED COMPANY)
CATALOG NUMBER
SEED PER PACKET OR SEEDS SOWED
WEEKS TO LAST FROST DATE OR PLANTING OUT DATE
DAYS TO GERMINATION
COVER SEED?
DATE SEEDED
DATE TRANSPLANTED
NOTES:
ACTUAL GERMINATION DAYS, % GERMINATION, SEED
REQUIREMENTS, CROP FAILURE, ETC.
TIMING YOUR PLANTINGS RELATIVE TO L.F.D.
USING INFORMATION ON CHARTS AND SEED
PACKS
SEED STARTING WORKSHEET
SEED NAME
SPECIES, CULTIVAR
SOURCE
SEED CO.
CAT
#
SEED
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PKT
WEEKS
TO
L.F.D.
DAYS
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GERM
COVE
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SEED
DATE
SEEDE
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2010
DATE
TRNSPLD
NOTES:
Worksheet Seed Packet Information
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On the front of the pack you will be given the common plant name plus the specific
cultivar. Usually on flowers you will also be given the botanical name.
The maturity date will be given in days. For example on a lettuce pack, it will grow to
baby size in 28 days and fully mature in 52 days. These are excellent guidelines if you
intend to plant seeds so that they will mature in succession for a steady supply of
produce. The number of seeds in the package will be listed along with the sell by date.
The minimum germination in percentages, very helpful when a specific number of plants
are required. For example if you need 100 plants and the minimum germination is listed
at 85% you should plant more than 115 seeds to be sure that you get required 100.
Cultural information includes the following: germination temperature. If starting seed
indoors you can control the temperature of the heat mat or whatever source of heat that
you are using to ensure maximum germination. Planting depth, the depth that the seeds
need to be planted. Some seeds require light to germinate so you just need to lay them
on the soil surface and not cover them with anything. Some require total darkness so
that you need to cover the planting container so that no light is available until the seeds
germinate.
Scarification, this term applies to seeds that have a very hard outer coating. You need to
nick or break the outer covering so that moisture can penetrate and germination can
begin. This is usually accomplished by using a sharp knife or sand paper to penetrate
the outer coating. If this procedure is not followed on seeds that require it you will have
a very low or zero germination rate.
Stratification, this term means the seeds need to be exposed to a period of cold for a set
amount of time. This term usually applies to perennials and biennials. If the seeds are
not given a cold period, again you will have a zero or very low germination rate.
STARTING YOUR SEEDS
• PLANTING YOUR SEEDS
– PREPARING SOIL
– FILLING CONTAINERS
– SOWING SEEDS FOLLOWING EACH SEED’S
REQUIREMENTS
– COVERING SEEDS
– WATERING SEEDS
– PROVIDING HUMID ENVIRONMENT
– PROVIDING PROPER TEMPERATURE (SOIL)
– PROVIDING PROPER LIGHT
Preparing Planting Medium
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Loosen and dampen the potting mix before you put it into your seed starting
containers. It is easier to get a uniform level of moisture if you do it this way.
Dampen the mix to the consistency of a rung-out sponge. It should be wet, but
not dripping, with no dry lumps.
There are many good potting mixes available. Using a soilless potting mix
rather than outdoor soil is preferable because potting mixes don't readily
compact, don't contain weed seeds and don't have disease spores and other
possible problems.
Also, since new seedlings don't require fertilizer until they sprout their first true
leaves, you don't really need a mix with fertilizer already in it.
Filling Containers With Soil
• Use the pre-dampened potting mix to fill your seed starting
containers.
• Don't pack the potting mix into the container.
• Fill to about 1/4” from the lip of the container and tap the container
on the table top, to help the potting mix settle.
• Gently firm and level with a spoon or a small board.
Sowing Seeds in Containers
• Make sure you read the seed package for special instructions. Some
seeds may require a period of pre-chilling or soaking.
• Small seeds can be sprinkled on top of the potting mix. Larger seeds
can be counted out and planted individually.
• Use at least 3 seeds per container, since not all seeds will germinate
and not all that do germinate will survive. You can thin extras later.
Covering Your Seeds
• Cover the seeds with more dampened potting mix and then gently
firm again.
• Re-check your seed packet for information on how much potting mix
should go on top of the seeds. Generally, the smaller the seed, the
less you need to cover them.
• There are a few seeds, like lettuce, that require light to germinate
and should barely be covered with potting mix, if at all.
Watering Newly Planted Seeds
• Although the potting mix was pre-dampened, it is still a good idea to
spray some additional water over the newly planted seed. This
insures that the top layer of mix won't dry out and it also helps to firm
the potting mix and insure good contact between the seed the mix
Providing Humid Environment
Create a Greenhouse Effect: Your seeds are now ready to be
covered loosely with some type of plastic. This will help hold in
both heat and moisture. You can place the whole container into a
plastic bag or simply lay a sheet of plastic over the container. If
you have special seed starting trays with plastic covers, use
those.
Providing Proper Soil Temperature
• Heat: Move your container to a warm, draft free spot
and check it daily. Most seeds germinate best when
the soil temperature is between 70 and 75 degrees F.
The top of a refrigerator is an ideal spot or you could
consider purchasing heating mats specially made for
germinating seed.
Providing Proper Light
• Move into the Light: Your seeds and seedlings need between
12-18 hours of light each day. This may seem extreme, but
artificial light and even winter sun are not as intense as full
summer sun. The best way to insure regular long doses of light
is to attach your florescent plant lights to an automatic timer.
Plant lights should never be more than 2 – 4 inches above the
seeds or plants. It will not harm the plants even if they touch
the fluorescent lights.
MONITORING YOUR SEEDS
DAILY
– CHECK HUMIDITY – moisture on bag or
glass
– CHECK LIGHT CONDITIONS – 12-16
hours, 2-4 inches above soil
– CHECK HEAT CONDITIONS – maintain
proper soil temperature (65o, 70o, or 75o as per
seeds requirements)
– LOOK FOR GERMINATION – as soon as
you see germination, remove the cover or plastic bag
and bottom water if on the dry side.
Emerging Seedlings-First Signs of Growth
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Once your seedlings begin poking through the soil, they will start to
straighten up and unfurl. What look like two leaves will appear. These are
actually leaf-like structures, called cotyledons, that are part of the seed and
serve as food sources until true leaves are formed and the plant is capable
of photosynthesis. At this point you should remove your seedlings from their
plastic greenhouse environment.
• MONITOR
– LIGHT – 12-18 hours,
2-4 inches above seedlings
– MOISTURE – use tepid water,
bottom water when needed
– TEMPERATURE (air) - above 55o – 60o
(soil) >70o for good root development
– FERTILIZATION - none needed at this point
GROWING TO TRANSPLANT SIZE
As the seedling grows, the cotyledons will wither and what are called
the first "true" leaves will form. This is when your seedling begins
actively photosynthesizing. Since it is growing in a soilless mix, you
will need to give it some supplemental feeding at this point. Use a
weak solution of a balanced fertilizer or one high in nitrogen and
potassium, to encourage good roots and healthy growth.
If more than one seedling is growing in the same pot, either separate
the seedlings into individual pots or cut off all but the strongest
seedling. Don't try to pull out the extra seedlings, since this will hurt
the roots of the seedling you are keeping.
• LIGHT – 16 hours, 2” above seedlings
• WATERING AND FERTILIZING –
bottom water with a dilute fertilizer
solution using tepid water
• TEMPERATURE – warm soil, cool air
• AIR CIRCULATION – use a fan
to control fungus
TRANSPLANTING SEEDLINGS
As soon as seedlings have developed at least one set of true leaves
and are large enough to handle, they should be transplanted to
individual pots or spaced out in flats. This is called “potting up”.
Failure to transplant promptly results in crowded spindly seedlings
that can’t develop properly. Generally, seedlings are transplanted
with soil up to their cotyledons.
Many transplants will have to be “potted up” a second time to larger
size pots to maintain vigorous growth.
CARING FOR TRANSPLANTS
• LIGHT – At least 16 hours, fluorescent lights
2” or less above seedlings
• WATERING AND FERTILIZING –only
bottom water with a dilute fertilizer solution
• TEMPERATURE – no need for heating mats
and air temperatures of 55o to 60o for sturdy
compact plants
• AIR CIRCULATION – maintain use of a fan
to control fungus
HARDENING OFF TRANSPLANTS
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By the time you want to move your plants into the garden or sell them at
the plant sale, you should have stocky, healthy young plants in four or six
inch pots. But before you do either you will need to take a week to two
weeks to gradually introduce them to their new growing conditions. This is
called hardening off. It gives the plants a chance to acclimate to sunlight,
drying winds and climate changes that they will have to endure.
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Move the plants outside to a shady spot for increasing amounts of time,
several days in a row.
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Bring them in or cover them if the temperature looks like it will dip below 50
degrees.
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Gradually increase the amount of time they spend outside and the amount
of sunlight they receive until you see that they are growing strong and
appear ready to go out on their own.
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If they are in a greenhouse or cold frame they are used to sunlight and can
acclimate to temperature by leaving the greenhouse open and ventiliated.
PREGERMINATION
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Another method of starting seeds is pregermination. This method involves
sprouting the seeds before they are planted in pots (or in the garden). This
reduces the time to germination, as the temperature and moisture are easy
to control. A high percentage of germination is achieved since
environmental factors are optimum. Lay seeds between the folds of a cotton
cloth or on a layer of vermiculite in a shallow pan. Keep moist, in a warm
place. When roots begin to show, place the seeds in containers or plant
them directly in the garden. While transplanting seedlings, be careful not to
break off tender roots. Continued attention to watering is critical.
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When planting seeds in a container that will be set out in the garden later,
place 1 seed in a 2- to 3-inch container. Plant the seeds at only 1/2 the
recommended depth. Gently press a little soil over the sprouted seed and
then add about 1/4 inch of milled sphagnum or sand to the soil surface.
These materials will keep the surface uniformly moist and are easy for the
shoot to push through. Keep in a warm place and care for them as for any
other newly transplanted seedlings.
WHY START PLANTS FROM SEED ?
• STARTING FROM SEED IS LESS EXPENSIVE
• UNAVAILABILITY OF THE PLANTS YOU WANT
LOCALLY:
– QUANTITIES
– VARIETIES
• GROW PLANTS THAT ARE HIGHER QUALITY FOR
PLANTING
• HAVING PLANTS SUITABLE FOR YOUR PLANTING
SCHEDULE
• SATISFACTION OF GROWING YOUR OWN PLANTS
FROM SEED
• PLANT SALES
• JERRY BABSKI
• burgflem@yahoo.com
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