Over lunch this week we were discussing the difference between white
and green asparagus. The question was whether green asparagus is the
same species as the white or two different species, which is why they
would be different colors.
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| Purple, white, and green asparagus |
Oh,
the power of Google! I learned that white and green asparagus are the
same species but it's the way that they are grown that affects the color
of the vegetable. To grow white asparagus the farmers or gardeners
cover the entire shoot with dirt. Without sunlight, the asparagus stays
white.
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| Chlorophyll a molecule |
I remember learning in a Plant Physiology class at
NC State that it is the magnesium that is required for the synthesis of
chlorophyll, which makes plants green. The magnesium is connected to
the center of the chlorophyll ring and is the element necessary to
convert light into energy. In general terms, the magnesium molecule is
necessary for the formation of chlorophyll, which makes plants green.
Chlorophyll absorbs red and blue light, reflecting green light which is
why plants look green. If you are interested in learning more, check out
the website credits below, these are great resources for additional
learning!
Back
to the asparagus. The most abundantly grown are green in color, with
white less so and considered a delicacy. White asparagus are grown
mostly in Europe and South America and can be pretty hard to find in the
United States. There are even purple asparagus! This is a different
variety than the other two and is purple in color due to the pigment
called anthocyanin.
I really like asparagus, it is probably one of my favorite vegetables. I
didn't think to plant any in our garden this year mainly due to lack of
garden space. Maybe next year we will try to grow year-old asparagus
crowns. This vegetable is perennial, so it comes back every year. I
learned that the plants are monoecious, which means that the whole plant
is either male or female. The male plants are what you want if you are
looking for a more productive crop. Once established, the asparagus crop
is good for 20 to 25 years! The organicgardening.com website below has
some great tips for gardening asparagus, which we may try next year.
Asparagus Websites:
www.asaparagus.com.au/
http://www.huffingtonpost.com/2012/04/09/white-asparagus_n_1412329.html
http://www.organicgardening.com/learn-and-grow/asparagus-growing-guide
Asparagus photograph: www.dreamstime.com
Chlorophyll Websites:
http://www.naturalnews.com/024847_magnesium_medicine_insulin.html
http://www.wisegeek.com/what-is-the-connection-between-chlorophyll-and-magnesium.htm
Chlorophyll photograph: http://en.wikipedia.org/wiki/Chlorophyll