Woad--Sarah's
Natural Colour
I've been growing the natural
dye, woad, since 2000. In 2006 I grew woad at Joybilee Farm
for my first
science fair project. I had a nil indigo yield when I tried
to
dye directly with the leaves using the method in Rita Buchanan's book,
"A Dyer's Garden" (Interweave Press), a process originally suggested by
Beijerinck in 1900.
"Woad is Me, finding a permanent blue from
sustainably grown indigo"
In 2007, my project competed at the Canada Wide Science Fair (Truro,
Nova Scotia) in Junior Biotechnology and Pharmeceutical Sciences. I
determined that natural indigo was most colour fast when dyeing using
repeated vattings and oxidizations to lay down a dark colour, rather
than a single dip in a strong vat.
"Woad to a sustainable blue colourant, Phase 2"
I continued to grow woad
altering the growing conditions in an attempt to enhance the indigo
production in my harsh, zone 3, marginal growing conditions.
I
also changed my extraction method and found that the indigo yield was
greatly increased. In fact, my woad indigo yields were
essentially the same as the indigo yields obtained on prime agricutural
land in current scientific studies in Europe, but I am growing on land
that is considered marginal range land and receives summer frost.
I grow my natural dyes organically, unlike the scientific
studies.
In 2008 I took Phase 2 of my science
fair project, on growing natural
woad
indigo and extracting its dye, to the Canada Wide Science Fair
(Ottawa). My project won a bronze medal in Intermediate
Biotechnology and Pharmeceutical Sciences and a silver medal in
Intermediate Environmental Innovation, at the national level.
"Woad to a sustainable
blue, Phase 3"
I isolated two
high producing strains of woad (pastel) and have begun
hybridizing to enhance the indigo yield in my harsh growing conditions.
In summer of 2008, Phase 3 of my project, I found that the indigo yields of
plants selected for vigour in my harsh climate, had doubled
their
indigo yield -- averaging 4 grams per kg. of leaves. Tropical
indigo averages 5 gms of pigment per kg. of leaves so this result is
encouraging. Especially in light of the fact that
my woad
is growing on range land which is unfit for normal crop
agriculture, due to its short growing season, high elevation and incidence of summer frost.
In 2009 I took Phase 3 of my science fair project, on growing natural
woad
indigo and extracting its dye, to the Canada Wide Science Fair
(Winnipeg). My project won a silver medal in Intermediate Biotechnology
and Pharmeceutical Sciences and a silver medal in Intermediate
Environmental Innovation, at the national level.
"Woad to a sustainable blue, Phase 4"
In summer of 2009, Phase 4 of my project, I compared the indigo yield
of my hybrid woad strain with both of it parent strains -- the original
seed and the seed I saved in my growing conditions. As well as
testing Isatis indigotica, and Isatis glaca, from Norway, and my original North American strain of Isatis tinctoria.
It was the coldest growing season yet, in this the fourth year of
my project. But my hybrid woad strain demonstrated that indigo
yields in Isatis tinctoria can be improved by genetic selection and hybridization.
I
didn't compete with my project at the regional science fair in 2010.
There was much misinformation circulated by the Chief Judge of the
regional science fair as to why I didn't compete. Let me say only,
that phase 4 of my project was successful. My hand hybridized strain
showed an improvement in indigo yields over the landrace strains that I
originally tested in my project, even in the cold summer of 2009.
However, I am working on a bigger project -- a book about woad growing
and dyeing, that will benefit the fiberarts community. And in 2011, I
hope to begin working on my Certificate of Excellence in Natural Dyes
from the UK Handweavers and Spinners Guild.
"Woad to a Sustainable Blue, Phase 5"
There is still much genetic selection to be done, including weeding out
undesirable traits before my hybrid woad strain will be ready to be
released. Further, testing of indigo yields and growing variables
need to be done as well. I hope
to
perfect my hybridized strain of woad so that it will yield indigo in
temperate, marginal conditions at the same rate as tropical
indigo in its ideal climate zone, typically 5 gm of indigo per 1 kg. of
leaves. My current extraction method gives between 3 and 7
grams of indigo per kg. of leaves, of varying purity.
I
am also designing an on farm portable extraction unit, significanly
different than the extraction units currently being used in Europe
which give low indigo yields and unreliable purity. Should my
experimentation prove successful, it will be possible to grow Isatis tinctoria
and extract its pigment in the field, improving farm incomes on
marginal lands in Western Canada and leading to environmentally
friendly natural indigo production in Canada.
Canadian organically grown Hemp - linen blue jeans dyed with natural
woad indigo would be a sustainable future for fashion in Canada.
Woad isn't just a natural dye plant. It is also being
investigated for
its healing properties. It is anti-fungal, anti-viral,
anti-inflammatory and anti-tumour. It is an ingredient in a
medicine for HIV/AIDS. It has more gluco-brassicin, a potent
tumour fighting plant extract, than broccoli,
and this property can be enhanced through leaf wounding, and it is
being investigated as a cancer treatment.
The indirubin component of woad is being used as an anti cancer
treatment. Dyer's Woad Root Tea is used to fight cold and flu
symptoms and enhance immunity.
New: Woad Workshops -
Learn more about woad at our woad workshop:
Growing a sustainable blue -- The Woad Plant and its dye --
taught by Sarah and Christine Dalziel at Joybilee Farm in Greenwood, B.C. Canada
Website
credits: Thank you to my mom, Christine Dalziel, for designing
and setting up the templates on this website. Writing is the work
and copyright of Sarah Dalziel; Photographs are the work and copyright
of Sarah Dalziel except where Sarah is in the picture -- those
photographs were taken by Christine Dalziel.
Webmaster: Sarah Dalziel.
Last updated: April 29, 2010
©
2007 - 2010 Sarah Dalziel
