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8/9/2019 The Seed Garden Sample
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The
SEED
GARDENThe Art and Practice of Seed Savinedited by lee buttala & shanyn sieg
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2 THE SEED GARDEN
CONTENTS
IntroductIon • 000
The Art and Practice ofSeed Saving • 000
WHY SAVE SEED S • 000
BOTANY OF SEED SAVING • 000
Nomenclature and Taxonomy • Propagation
• Flowers • Pollination and Fertilization •
Fruits • Seeds
MATING SYSTEMS • 000
Mating Systems • Pollination Methods •
Insect Pollinators • Floral Diversity
STAYING TRUE: Seed Saving andVarietal Maintenance • 000
Open-pollinated Versus Hybrid Varieties
• Isolation and Pollination Management •
Population Size and the Maintenance of
Genetic Diversity • Rogueing and Selection •
Crop Improvement • 000
CULTIVATING FOR SEED • 000
Plant Lifecycles • Photoperiodism and
Vernalization • Timing and Spacing • General
Plant Culture • Seedborne Diseases • 000
HARVESTING AND
CLEANING SEEDS • 000
Harvesting • Cleaning Seeds from Dry-Fruited
Crops • Cleaning Seeds from Fleshy-Fruited
Crops • 000
SEED QUALITY, STORAGE AN
GERMINATION • 000
Seed Quality and Longevity • Seed
Content • Home Seed Storage • GeTests • Seed Dormancy
THE SEED GARDEN • 000
Planning for Seed Saving • Choosin
• Seed Saving in the Vegetable Gar
Beginner Recommendations • 00
Plant Profiles • 000
INTRODUCTION • 000
Common name directory • 000
Plant Profiles • 000
APPENDIX: Seed SavIng MaSter tab
APPENDIX: gerMInatIon table • 00
APPENDIX: REGIONAL AND C LIMACTIC
conSIderatIonS • 000
APPENDIX: legalItIeS • 000
APPENDIX: Seed Screen SIzeS • 000
gloSSary • 000
Index • 000
acknowledgeMentS • 000
8/9/2019 The Seed Garden Sample
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4 THE SEED GARDEN The Botany o f Seed Saving
For some gardeners, an understanding of botany can
transform the magical and mysterious path of a plant—f
seed to seedling, from flower to fruit, and back again int
seed—into something more measured and technical tha
wondrous and spiritual. But as one comes to understand
the scientific underpinnings within the formation of a se
this deeper understanding of botany only works to reinfo
a belief in the miraculous processes at work in the garde
bringing with it a deeper appreciation of the merging of
and science which is at play in the horticultural univers
in the tradition of seed saving.
The
BOTANY of SEEDSAVING
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8 THE SEED GARDEN The Botany o f Seed Saving
they then all became
members of the newly
named Brassicaceae
family. Many garden-
ers – who remember
these crops as part of
the original family –
still commonly use
the term crucifer
when speaking of this
group of plants. Whilethese reclassifications
may be frustrating to
a gardener who has
learned the old name
of a genus or family,
they rarely impact the
work of a seed saver.
Propagation As most gardeners know, plants can be repro-
duced in more than one way. When a gardener
is interested in collecting seed and using this
seed to grow more plants, the process at play is
known as sexual reproduction because genetic
material from two parents are being combined to
create new offspring in the
form of seeds. These seeds
will become plants that
have characteristics of both
parents because they share
their DNA. But many plants
can also be reproduced
asexually through vegeta-
tive propagation, which
typically involves taking a
part of the plant – a root,
a leaf, a stem, or a division
of a plant – and inducing
it to develop into a plant of
its own. These plants willbe genetically identical to
their parent and this process
is used in the propagation
of many perennial and
Conversely, it
may also come as a
surprise that ‘Rouge
Vif D’Etampes’
pumpkins and ‘Winter
Luxury’ pumpkins
belong to the same
genus (Cucurbita), but
are separate species.
‘Rouge Vif D’Etampes’
pumpkin is aCurcurbita maxima
cultivar , while ‘Winter
Luxury’ pumpkins are
a variety of Cucurbita
pepo. Although closely
related, and referred to
by the same common
name, these two
pumpkins will not interbreed with each other.
Becoming familiar with the botanical names of
plant species is essential to the seed saver as it tells
of a relationship between plants in a manner that
common names such as collards and broccoli, or
pumpkin, do not.
Occasionally, the taxonomic classification
or name of a collection of plants changes as
scientists’ understanding of
the relationships between
plants deepens and evolves.
For example, many spe-
cies belonging to the
Brassicaceae family (a family
is a collection of genera that
are closely related) used to
be known as members of the
Cruciferae family, named
after their characteristic
cross-shaped, cruciform,
four-petaled flowers. When
scientists found that these
plants, which includevegetables such as kale,
broccoli, cabbage and
cauliflower, were part of a
broader family of plants,
that surround a rose bud before it opens—protect
the flower bud during development, while the
petals can play a role in reproduction by attract-
ing pollinators with their patterning and color.
While these parts can encourage the re pro-
ductive process, they are considered accessory
parts and are not needed specifically for sexual
reproduction. However, for seasoned seed savers,
petals can often hold clues as to how a specific
plant approaches pollination.
Not all flowers are created equally and whattype of flowers a plant has impacts how it can
reproduce. Botanically, a perfect flower—which
is also called a bisexual flower-- must have both
female and male reproductive parts, the pistil
and stamen, in one flower. An imperfect flower
is unisexual, and is commonly referred to as
either a female flower or male flower. Plants that
have both unisexual female flowers and unisexual
male flowers on one plant are known as monoe-
cious (this term derives from the Latin for one
household, meaning male and female flowers
live on the same plant). Corn is an example of a
monoecious crop plant, where the male flowers
woody plants, as well as with a few vegetables
such as Jerusalem artichokes and sweet pota-
toes. However, relatively few vegetable crops
are primarily reproduced vegetatively. Most
are grown from seed, and for the seed saver, a
general understanding of how a plant flowers and
produces seeds is necessary for the preservation
of coveted varieties of vegetables.
FlowersMany gardeners consider flowers as things ofbeauty, much more than as a sum of their botan-
ical parts, but in the life of a plant, the role of a
flower is anything but decorative. A flower is the
seed and fruit producing structure within a plant.
Within the structure of flowers there are male
and female reproductive parts that allow a plant
to create offspring in the form of seeds.
Flowers, botanically defined most simply as
the reproductive organs of angiosperm plants,
provide a useful tool for understanding how read-
ily a species will reproduce and what is needed
for it to succeed in making it through the various
stages of sexual reproduction in plants: pollina-
tion, fertilization, fruit and seed set.
The female reproductive organ or the female
part of a flower is known as the pistil. The pistil is
comprised of three parts, the ovary, the style, and
the stigma. The stigma is the receptive surface at
the top of the pistil that receives the pollen from
the male parts of a flower, and it is connected to
the ovary by means of a tubular style. The ovary
houses the ovules, which contain egg cells and
will develop into seeds if fertilized. The ovary
itself matures into a fruit upon fertilization.
The male reproductive organ of the flower
is called the stamen. The stamen is made up of
the anther and the filament. Pollen grains, which
supply the sperm cells for the fertilization of the
ovules, are produced in and released from the
anther, which is presented on the end of a long,protruding stalk, or filament.
The flower also has petals and sepals, perhaps
the most recognizable parts of a flower. The
sepals – such as the small green modified leaves
Although this flower is from a variety of cabbage, it is
indistinguishable from the flowers of other members
of the species Brassica oleracea, including Brussels
sprouts, collards, broccoli, cauliflower, kohlrabi, and
European kale. These crop types are capable of repro-
ducing with one another but any offspring from such
crosses would unpredictable as to their appearance.
Common names can prove confus-
ing. Both of these fruits are known as
pumpkins, but as they are not from the
same species, these two varieties, tk and
tk, cannot breed with one another and
produce fertile offspring. For this reason,
knowledge of a plant’s botanical name is
of use to the seed saver in understanding
which plants may cross or interbreed.
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10 THE SEED GARDEN The Botany o f Seed Saving
Watching a honeybee alighting on a flower or a hummin
floating in front of a blossom, foraging for nectar or polle
is one of those moments that takes a gardener away from
everyday tasks of weeding and cultivating, and reminds u
the special relationship between plants and their pollina
By delving more deeply into this universe and understan
the anatomy of a flower and the method by which a spec
is pollinated, seed savers gain insight into the various ma
systems of some of their favorite species and cultivars.
MATING SYSTEMS
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12 THE SEED GARDEN The Botany o f Seed Saving
Four species of squash are normally grown as
garden vegetables. They share the same pol-
lination mechanisms and floral anatomy, and
respond to the same process of hand-pollination.
Although squash plants bloom continu-
ously over the course of the growing season,
each individual flower opens for just one day,and hand-pollination requires some planning
and attention to timing to ensure success.
Hand-pollinating squash plants occurs on two
consecutive days – beginning in the late after-
noon when flowers that are just about to open
are identified and secured shut, and completed
the next morning when the flowers are pollinated
manually.
Identifying flowers that are about to open
takes some practice, but is relatively straightfor-
ward. When in bud, the squash blossoms are
greenish yellow or pale creamy-yellow in color.
On the day before they open the fused petals will
begin to split open at the top and a small seam of
yellow will typically be visible.
Squash plants are monoecious, and both
male and female flowers need to be secured shut.
Female flowers are easily identified by visible ova-
ries, which resemble a small squash, located just
below their blossoms; the flowers without ovaries
are male. The male flowers, which provide the
pollen, should be secured shut with flagging
ribbon, tape, clothespins, or any other material
that will prevent the petals from expanding and
allowing insects access to their reproductive
organs. A flag is often inserted in the ground next
to each of the sealed flowers so that they can be
easily found the next morning amongst all of
the foliage. Follow the same process with female
flowers keeping in mind that care must be take
to leave enough of the petals intact to secure theblossoms again after hand pollinating. This will
ensure that the seeds produced are the product of
the manually transferred pollen and not from nat-
urally occurring insect pollination that can occur
on the same day after hand-pollination, while the
stigma is still receptive.
The following morning, hand pollination
is carried out during the time of day when the
squash blossoms are normally open. Flowers
can open just after dawn, and remain open until
early afternoon, though the exact timing andduration is influenced by environmental condi-
tions. The male squash flower, typically borne
on a long peduncle (stalk), should be picked
and brought to the female flower. First open the
male flower and remove the petals of the male
flower entirely, leaving the anthers and pollen
exposed upon the end of the peduncle. Moving
quickly, carefully open the female flower– the
goal is to complete the hand pollination process
before any bees intervene – and brush the pollen
from the anthers onto the entire surface of the
stigma. The pollen grains are large enough that
they will be visible on the stigma after pollina-
tion. Close the female petals up again and tape
them shut, ensuring that there are no openings
that pollinating insects can get through. The
petals will shrivel, and, along with the tape, will
likely fall off after fertilization is complete and
the fruit begins to develop. Tie a ribbon or some
other weather-resistant marker to the stem of the
hand-pollinated flower so the isolated fruit can
be easily identified at harvest.
Hand-pollination can be done using just one
male flower for each female, but some gardeners
choose to transfer pollen from the anthers of two
or three male flowers to the receptive stigma of a
female flower to effectively include more plants
in the reproductive population. If possible,
choose males flowers from a separate plant than
the one bearing the female blossom.
Expect low rates of successful polli nations whenfirst learning to hand pollinate a species. It is gen-
erally a good idea to pollinate at least four times
as many flowers as the number of fruits from
which one wishes to collect seed.
1. In the afternoon, identify male and
female flowers about to open.
2. Secure female blossom closed. 3. Secure male flower clo
4. Mark location of sealed flowers. 5. The following morning, collect sealed
male flowers from plants and locate
flower to be pollinated.
6. Working quickly, remo
male flowers and open fe
7. Still working quickly, brush pollen from anthers onto entire
surface of stigma. Pollen grains should be visible.
8. Thoroughly seal pollin
Mark flower for seed col
fruit can be readily ident
8/9/2019 The Seed Garden Sample
8/914 THE SEED GARDEN Lactuca sativa
a 2,000 year-old Roman recipe calls for using
lettuce to make a dish fairly recognizable to pres-
ent-day salad eaters, a collection of leaves dressed
with herbs, oil, vinegar and pepper.
GROWING LETTUCE FOR SEED
A self-pollinating annual with minimal isolation
requirements, most lettuce varieties will flower
and set seed readily in one growing season.
In fact, a moment gardeners typically lament
-- when flower stalks of lettuce emerge and the
leaves turn bitter – is the beginning of the seed
production process. These branched flower stalks
may reach 3 feet tall or more, but do not typi-
cally require staking. Lettuce plants being grown
for seed should be spaced 15 inches on center.
Lettuce can easily be planted at typical garden
spacing and harvested for eating with several
plants being left to develop into a seed crop.
Leaf lettuces being grown for seed may be lightly
harvested. For the best seed harvest, gardeners
should time sowing so that plants reach full size
prior to flowering (cool temperatures of approxi-
mately 60F are ideal for lettuce growth), so thatflowering coincides with a period of warmer tem-
peratures (ideally around 70F). In many northern
parts of the country, this is accomplished with
a typical spring planting, with flowering and
ranges from the burgundy red leaves of ‘Lolla
Rossa’ through blue and lime green to the
chartreuse of the butterhead variety ‘Mantilla’.
In addition, some varieties have speckled, tinted,
or blushed leaves such as the aptly named
‘Sanguine Ameliore’ that has foliage with a splash
of blood red. Leaves range in shape and formfrom the smooth, lanceolate leaves of ‘Amish
Deer Tongue’ and the lacy frilled leaves of ‘Reine
De Glace’ to the deeply serrated leaves of ‘Green
Oakleaf.’
Lettuces are grouped into categories. Loose-
leaf varieties, sometimes simply called leaf
lettuces, form loose, open heads and the full
spectrum of leaf colors and shapes can be found
among these types. They are also often harvested
young and as cut-and-come-again lettuce crops.
Butterhead, or bibb, lettuces such as ‘Ella Kropf’
form small, loose heads with leaves known for
their smooth, buttery texture. Crisphead, or
iceberg, cultivars develop a head of tightly over-
lapping leaves and romaine, or cos, lettuces are
easily recognized by their thick leaves with large
mid-ribs arranged into tall, upright heads.
A lesser-known member of the species
Lactuca sativa is celtuce, also known as Chinese
lettuce, asparagus lettuce, or celery lettuce.
Grown for its distinctive thick edible stem,
this variety is harvested when its stem is about
1½ inches thick and is used in stir-fries.
Oilseed lettuce, seldom seen in home gar-
dens, is cultivated for its seeds that are pressed to
extract cooking oil. Oilseed lettuce seeds yield up
to 35% of their weight in oil.
HISTORY
Thought to have originated in what is pres-
ent-day Iran and Turkey, archaeological evidenceindicates that lettuce was grown in Egypt more
than 6,000 years ago as an oilseed crop and as an
aphrodisiac. Lettuce gained status as a popular
vegetable in ancient Greece and Rome, and
Lactuca sativaLETTUCE
lettuce seeds can be viable for up to six
years, plant it out in the years ahead. And
with so many varieties of open-pollinated
lettuce available, seed savers have many
options from which to choose.
CROP TYPES
Primarily coveted as an essential ingredient in
salads, most lettuce is grown for its edible leaves
that range in color, shape, and form. Leaf color
Most gardeners have grown lettuce close to the point that seed can be collected wi thout even
realizing it. As a self-pollinated crop that typically bolts, flowers, and sets seed in one season
without taking over a huge amount of vegetable garden real estate, this is an easy crop for the
first-time seed saver, particularly if one starts with a loose-leaf variety. Many gardeners simply
allow a select few of their plants to set seeds, clean and store what they collect, and, since
‘Tennis Ball’ lettuce, which was grown by Thomas
Jefferson at Monticello, can be planted in an orna-
mental border along with ‘Bull’s Blood’ beets and
nasturtiums.
For many g
of lettuce b
its leaves h
unpalatable
stalks serve
savers of an
of ripened s
FAMILY: Asteraceae
LIFECYCLE: Annual
SUGGESTED SPACING: When growing lettuce for seed,increase spacing to at least 12 inches (30 cm) oncenter
OTHER REQUIREMENTS: None
FLOWER TYPE: Perfect, self-fertile flowers grouped intoinflorescences called heads. Multiple heads arefurther arranged in a panicle.
POLLINATION: Self-pollinated (autogamous)MATING SYSTEM: Almost entirely self-pollinating; pollina-tion typically occurs before the stigma emerges.
ADDITIONAL CROSS-POLLINATION CONCERNS: Lettuce iscross-compatible with wild lettuce (Lactuca serriola),but the self-pollinating nature of the species makesthis of little concern. Keep wild lettuce weededwithin lettuce beds or plantings.
FRUIT TYPE: Dry, indehiscent, single-seeded fruit(achene). The fruit acts as a seed for propagationpurposes.
SEED MATURITY: Seed maturity occurs after market matu-rity, when the pappus emerges. At maturity, seeds arereadily dispersed by wind.
SCREEN SIZES: 3 ⁄ 64 × 3 ⁄ 4–6 ⁄ 64 × 3 ⁄ 4 inch (1 × 20–2 × 20 mm)
EXPECTED SEED LIFE: 6 years
ISOLATION DISTANCE
Seed Saving:10–20 feet(3–6 m)Commercial Production: 50 feet (15 m)
POPULATION SIZE
For Viable Seeds: 1 plantFor Variety Maintenance: 5–10 plantsFor Genetic Preservation: 20 plants
Lactuca sativaThree times actual size
8/9/2019 The Seed Garden Sample
9/916 THE SEED GARDEN Lactuca sativa
cold temperatures immediately after germination
have all been cited as additional or compounding
influences.
Flowering triggers vary so much from
variety to variety that there is no exact formula
for predicting flowering times, but some gen-
eral patterns between market classes are fairly
well accepted. Celtuce and loose-leaf types are
typically the earliest flowering, while the heading
types flower later—with crisphead lettuces typi-
cally requiring the longest season to flower. Theflower stalks of tight heading types occasionally
need assistance emerging, which can be done
by cutting an X in the head as it reaches market
maturity or by cracking the head open with a slap
of the hand. Beginner seed savers are advised to
start with a loose-leaf variety, preferably one they
have grown to full size maturity in their garden.
Most varieties of lettuce mature individual seeds
12 to 21 days after fertilization.
VARIETY MAINTENANCE
When growing lettuce for seed, a separati on
of ten feet between varieties is recommended
primarily to prevent any unwanted crossing that
may occur as a result of flowers from adjacent
plants rubbing against each other, but given the
short flowering time of individual blooms and
the shape of the flower, home gardeners may
choose to reduce this recommended distance if
seed is being collected for personal use. Although
gardeners have been known to harvest seeds from
just one or two plants, they should attempt to har-
vest seeds from at least 5 plants for personal use;
with the optimum population size for the genetic
preservation of a healthy variety being 20 plants.
As isolation distances are minimal, there i s little
to no need for controlled pollination.
Off-type and especially weak or diseased
plants should be rogued before seed production
and collection, and lettuce crops may be checked
for head type and shape, leaf type, leaf color,and texture. Some traits to consider for variety
improvement include early vigor, color and leaf
form, flavor, head type, disease and pest resis-
tance, and bolt resistance.
seed set occurring during the warmer months
of summer, but gardeners in other regions may
find that this is best achieved at the time they
are accustomed to planting their main lettuce
crop--possibly in late summer, fall, or even winter
depending on regional conditions. Leaf lettuce
plants grown for seed probably need to remain in
the garden at least xx days to reach full maturity.
By choosing lettuce varieties suited to different
regions of the country, seed savers can help
ensure successful seed production.By limiting or eliminating overhead watering
during seed production, a gardener can improve
seed quality. Commercial growers in wet regions
of the country collecting larger crops even
protect their lettuce from rain with a hoophouse
or overhead cover, but for the home seed saver
these techniques are optional.
FLOWERING, POLLINATION,
AND SEED SET
Because the perfect flowers of lettuce have fused
anthers that shed their pollen in towards the
stigma, they are almost completely self-pollinat-
ing. Like other members of its Asteraceae family,
what appears to be a single
flower on a lettuce plant is
actually a composite flower. 15
to 25 individual flowers, known
as florets, are arranged into an
inflorescence known as a head;
each floret opens for just one
day, and usually just for a few
hours. If fertilized, each floret
has the ability to produce a
single seed and given that there
are numerous heads on each
plant, which can flower succes-
sively over a period of 40 days
or more, a single lettuce plant
can produce a thousand seeds
if properly harvested. Bolting,the setting of a flower stalk, can
be triggered by increasing day
length, but high temperatures,
moisture stress, and exposure to
For many gardeners, the sight of
lettuce bolting signals that its leaves
have turned bitter and unpalat-
able but these flower stalks serve
a reminder to seed savers of an
impending harvest of ripened seed.
The emerging pappus signals that seed matu-
rity is approaching. At full maturity, achenes
will be dispersed by wind currents.
Another method
allows one to harvest all
at once and is used by
commercial growers.
When approximately
60-75% of the seed heads
are mature, plants are
pulled up, roots and
all, and transitioned to
a space where they can
continue drying. Plantsare placed on landscape
fabric with seeds heads
pointed toward center
of cloth and then left to
mature and dry for about
a week prior to cleaning.
In humid or rainy locales,
this process may be modi-
fied by putting plants into
bags or tubs and bringing
them inside a garage or
other protected space.
CLEANING
Cleaning methods vary depending on how the
seed was collected and how much chaff is pres-
ent. If achenes were gathered by shaking plants
or grabbing seed heads, there should be relatively
little chaff and cleaning techniques can focus
on separating the seed from the pappus. Lightly
rubbing the clusters together between your hands
or against a screen should provide enough force
to separate the seed and pappus while not dam-
aging any seeds. Once separated, the seed lot can
be winnowed, but as the seed is often about the
same weight as the pappus, this is not always the
most successful separation technique. Screening
can prove quite effective at separating seed.
While lettuce is a crop often suggest ed for begin-
ner seed savers because of the ease of triggering
seed production and the ease of collection, it isone of the more challenging to clean. But, if the
seed is for personal use, and was disease free and
thoroughly dried, storing an imperfectly cleaned
lot is likely not to prove detrimental.
HARVEST
The sequential flowering
pattern in lettuce gives
rise to a similar pattern
in seed maturity with
seed developing over an
extended period on each
flower branch. When
the seed “feathers”, or
produces a light grey
pappus -- tufts of hairs oneach seed that facilitate
wind dispersal, the seed
is mature.
The fruit and seed
of lettuce are so closely
interdeveloped that they
are almost indiscernible.
The seed remains in the
fruit at maturity—it is
actually the single seeded
fruit (achene) that is
sown. Although the fruits
are indehiscent and do
not break open, seed should be collected before
it is dispersed by wind.
A simple seed gathering technique, useful if
seeds are being collected from just a few plants, is
to hand harvest individual seed heads and trans-
fer into a small bag or container. Provided the
pappus has formed but not yet fulfilled its seed
dispersal function, taking hold of the pappus and
picking it along with the seed is an easy method
of hand collection. Each seed head should
produce about 15-25 seeds, making this an ideal
method for a gardener to collect a small quantity
of seeds for home use, and more can be collected
easily as other seedheads on the plant continue to
mature over the coming weeks.
Another technique involves bending fruiting
branches into a paper bag, and gently shaking
to dislodge seeds. This process is slightly moreefficient and can be started when about one third
of the seed heads are mature and can be repeated
every week or two until the desired amount of
seed has been collected.