Green is Good for Labor
Have you noticed the recent attacks on both our environmental protections and our labor
laws? It seems this past year brought many attempts to weaken clean air and water
standards as well as remove collective bargaining rights all across the country.
Luckily, we can engage with these issues hand in hand: insuring that we have clean air
and clean water creates jobs, and protecting well-paying American jobs promotes
environmental sustainability.
But, you may be asking, how can one work towards helping the other?
Environmentalists are a strong voice in the labor movement. For example, they recognize
that decreasing our dependence on foreign oil and fostering a domestic renewable supply
has created a surge of jobs in clean-tech manufacturing and installation. Creating greener
and safer manufacturing methods in all our industries, while streamlining our use of
limited resources, continues to help grow the economy.
And the beautiful thing is that this focus on environmental sustainability can make our
economy more efficient and competitive without sacrificing labor standards.
We recognize this fact here at Growstone. We continually strive to make our
manufacturing process more sustainable: no excess water or energy is used in the
process. We take waste glass from the Albuquerque landfill and turn it into a valuable
high-performance horticulture product. Patrick Beare, VP of Sales here at Growstone, is
proud of the progress we have made thus far. “Until Growstones came along,” says
Beare, “many growers used products like perlite and Hydroton which are strip-mined,
causing ecological damage, then shipped long distances to reach the market. Growstones
produce better results not only for plants but for the planet.”
Equally as important, we pride ourselves on being American made. Our products
highlight the quality of American technology and the skills of the American worker. We
believe that a business must encourage stronger occupational safety standards, health
insurance for their workers, and paid vacation and sick days. We want Growstone to be a
place our employees like working.
Our success gives back directly to our local community. Recent growth has led to a 50%
increase in our workforce. Mike Langone, our CEO, reports that we are working with the
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state as well as the National Guard to find qualified workers. “We are hoping to give jobs
to returning veterans. We believe in the quality of the American workforce and the
quality of Made in America products. As a matter of fact, we just purchased a crushing
machine from a local Belen, New Mexico company. It’s important to us to go local
whenever possible.”
So let’s go forward together and demand better standards of living, higher environmental
standards, fair wages and the best working conditions.
Green is green in more ways than one. What’s your green thumb greening in your
neighborhood?
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Are Landfills the Mines of the Future?
There are greater concentrations of precious metals in our e-waste than there are in the
ground. And it’s a lot cheaper and cleaner to get things out of e-waste than starting a
giant mining operation. Where would you rather get the materials for your next gadget?
The mountain of electronic waste rising around the world is a gold mine–literally. Urban
deposits of e-waste (discarded computers, phones and other electronics) contain 40 to 50
times the concentration of precious metals compared to ore mined from the ground at
great cost to the environment, human health, and buyers of latest gadgets. We should
mine it our e-waste, then, rather than the stuff in the ground.
That’s the message from the “e-Waste Academy” co-organized by the United Nations
University and the Global e-Sustainability Initiative (GeSI). Despite the 21 billion dollars
of gold and silver embedded in modern electronics each year, not to mention copper, tin,
cobalt, and palladium and other metals, only a fraction of which is ever recovered. For
example, 80 to 85% of gold in e-waste is lost due to crude (and dangerous) dismantling
processes in developing countries and ineffective collection systems in developed
countries (which are the source of most e-waste).
“Rather than looking at e-waste as a burden, we need to see it as an opportunity,” said
Alexis Vandendaelen of Umicore Precious Metals Refining at the meeting.
The global business for recovering precious metals from electronics–expected to hit
$34.5 billion by 2018–is nowhere near as efficient as the system to distribute high-tech
goods in the first place. Despite record high prices for metals such as gold (now five
times the price per once in 2001), the majority of metals in e-waste is still landfilled or
lost, rather than recycled.
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That may change. GeSI is establishing international best practice for e-waste handling.
European Union and the US have both tightened standards to ensure at least a portion of
electronics sold in the market make it back to a recycling center (85% in the EU by
2019). Even developing countries such as India, a major destination for international ewaste, now demand old computers and electronics end up at authorized collection sites.
We may look back in wonder at how we let such a precious resource go to waste. One era’s trash is
another’s treasure. Source: Fast Company
We, at Growstone, couldn’t agree more.
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Made in (Green) America
As the trend towards outsourcing overseas continues, less and less of our products are
being manufactured in American. As a result it is increasingly difficult to find Americanmade goods. But there are a number of small businesses that are dedicated to creating
manufacturing jobs here at home. And unsurprisingly, buying these products is often the
most sustainable choice you can make as well.
Here at Growstone, we pride ourselves on being both 100% recycled and 100% American
made. A winning combination! Unlike our competitors, Growstones are made right here
in our backyard, which creates jobs and contributes to a vibrant local economy.
Moreover, our carbon footprint is minimal since we ship from sunny Albuquerque, NM
and the raw material for our product is recycled glass. No strip-mining for us, unless you
count mining of the local landfill. Our manufacturing process not only shows the quality
of American technology but the skills of the American worker as well– something Mike
Langone, CEO of Growstone, holds in high regard. “We are committed to growing our
company and growing our workforce right here in Albuquerque.”
According to Julie Reiser, president and co-founder of Made in USA Certified, “Buying
Made in USA is not just a passing trend. It truly is something we as consumers, business
owners and even government can do to support small to mid-size businesses”. She goes
on to explain the importance of small businesses in boosting our economy, “Small
businesses are responsible for two out of every three new jobs created in the U.S. We
need these small to mid-size businesses to flourish and grow as they are our innovators,
our makers and job creators. Making it in America, supporting U.S. manufacturing and
buying American is one thing we can all do today to help keep the American dream alive
and well.”
Still not convinced? Check out these 7 reasons from Americansworking.com as to why
buying American is the right (and green!) thing to do.
1. Jobs – Above all else, when you buy American you save or create AMERICAN
JOBS! These are the jobs that are at the foundation of our economy, and have
unfortunately been moving overseas, but by buying American you can help to reverse
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that trend. According to Moody’s Economy.com, if every American spent just an extra
$3.33 on U.S. made goods every year, it would create nearly 10,000 new jobs.
2. Environmental – Many of the top countries where our goods come from have little or
no regulations to protect the environment, and the manufacturers have no regard for the
earth and they pollute and abuse the soil, air, and the water. When you buy American you
know there are regulations in place to protect the environment so our children can
appreciate this beautiful country as much as we do.
3. Human Rights – The countries the United States import from often have nonexistent
standards regular working conditions. Many of the factories producing US bound goods
are worse than our prisons, and filled with children working extremely long days. No one
wants to support that, and by buying American you know you aren’t we have regulations
and agencies in this country to prevent those types of atrocities.
4. Democracy – Americans believe in and stand up for democracy whenever we can, and
by choosing to buy American you are supporting the ideals of democracy.
5. Conservation – When buying products that are produced overseas built into the price
is the cost of shipping that product all the way from that country to the United States,
usually crossing the Atlantic or Pacific Ocean. This wastes an extremely large amount of
petroleum and produces unnecessary emissions into the atmosphere.
6. Domino Effect – When you buy American that money stays in the United States. That
money goes to pay the wage of many people that are directly or indirectly responsible for
creating your product. Each of them in turn spends this money on goods (hopefully
American made) and services, and the cycle continues. The more you buy American, the
more the economy is stimulated, and the more jobs are created. Plus, American workers
pay taxes on wages earned in America.
7. MORE JOBS – For every manufacturing job there are FIVE additional jobs created.
Do the math. Dollar for dollar it is a great investment in this amazing country!
Sounds like something we should all support.
As a consumer, you can’t go wrong with a product that is both green and American made.
Growstones are an American success story. When we all work together our economy, our
planet, and your plants will thrive! Tell us how else you are supporting a local green
economy. See you on Facebook!
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20 Sustainability Trends for 2013
Here is a list of 20 sustainability trends that are changing the business landscape.
We’re keeping our eyes on these…
1. From economic collapse to a green economic recovery. Interest in all things “green”
continues to grow as the economy sinks. About 34 percent of people are now more likely
to buy environmentally responsible products, and 44 percent say that their environmental
shopping habits have not changed during this downturn. Businesses are realizing the
ability to minimize costs through environmentally conscious operations.
2. From carbon footprint confusion to footprint awareness. More than half of the
global population is aware of the term “carbon footprint,” up from 38 percent in 2007. As
this awareness grows, consumers will likely drive the sustainability market by demanding
low carbon products.
3. From carbon offset doubt to market development. More companies will continue to
offset carbon emissions, with an expected growth in the global carbon offset market of 20
percent in 2009. Despite this prediction, Clownfish hope that there will be a stronger
trend for direct reductions rather than offsetting; as the old saying goes, “prevention is
better than cure.”
4. From carbon-centric to water-centric. The UK has become obsessed with carbon
footprints, but now the term water footprint has entered the corporate vocabulary. About
2.6 billion people have no access to clean water, a problem not isolated to developing
countries. Businesses will no longer be able to ignore their water use and efficiency.
5. From direct water use to embedded water use. According to Waterwise, the average
person in the UK directly uses about 150 liters of water per day. But there is an indirect
use, which is about 23 times higher at 3400 liters per day, with 31 percent embedded in
industrial goods and 65 percent embedded in food To reduce this indirect usage,
consumers will be calling on businesses to make changes to their products.
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6. From high-energy use light-bulbs to light-sensors. A recent survey of over 2000
lighting and electrical experts has found that occupancy sensors are the most
recommended energy saving office tool. They can save an average of 30 percent in
lighting costs. Expect more companies to be adopting energy saving techniques,
particularly as companies tighten their purse strings in the recession and energy bills
continue to fluctuate.
7. From cheap to costly carbon car taxes. European taxes on carbon emissions for new
cars are becoming stricter. Suppliers will need to be engaged and made aware of the
realities that they will face when this legislation is passed.
8. From fast fashion to slow fashion. Consumers are beginning to steer away from
cheap, disposable items and appreciate the value of investing in ethically-sourced,
organic and fairtrade fabrics. Consumer awareness will continue to grow, and shoppers
will no longer consider products that cause environmental destruction or promote
unethical practices to be the best. Luxury fashion will begin to associate environmentally
and socially responsible products with status.
9. From landfill waste to lack of space. Landfill sites for London’s non-hazardous
rubbish are likely to be full by the end of 2010, and other landfill sites will run out of
capacity by 2013. Europeans hope to achieve a 75 percent reduction in landfill waste
between 2005 and 2010, a further 50 percent by 2013 and 35 percent by 2020. So
companies will have to seek reductions in waste or be forced to pay up.
10. From energy excess to energy efficiency. The EU’s prEN 16001 energy efficiency
standard, out in 2009, will extend the scope of the ISO 9001 and ISO 14001
environmental standards into energy management to help companies set up continuous
improvement processes for efficient energy use. The ISO is planning to do likewise with
a new ISO 50001 standard by 2011.
11. From energy efficiency standards to legal requirements. New energy laws are
likely. A draft EU standard for energy efficiency services was published in March 2009
and outlines standards for calculating energy consumption, energy audit methodologies,
and energy certificates, which the EU hopes may be tradable in the future.
12. From fossil fuels to renewables. Renewable energy is a focus of 2009 as the
European Investment Bank increases lending to develop renewable energy schemes.
According to Morgan Stanley’s Green Market Penetration forecast (2007), the
renewables trend is going to continue developing; revenue from alternative energies
could top $500 billion in 2020 and world-wide sales from alternative energy sources
could reach $1 trillion by 2030.
13. From printed papers to digital development. Digital marketing has provided new
tools for brands to reach their audiences; the development of online videos, social
networks, podcasts and games, highlights that the digital marketing space will continue to
expand. Brands will increasingly use online spaces to communicate with consumers. It’s
no longer a one-way narrative, it’s about a two-way conversation.
14. From greenwashing to green authentification. Complaints about the misuse of
green terminology in advertisements have increased dramatically in recent years. The
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most common claims being challenged referr to carbon reduction, cradle-to-grave, and
green energy sources. This year will see the development of advertising standards and an
increasing requirement for brands to have claims underpinned by facts.
15. From creative carbon labels to consistent carbon labeling. Carbon labeling
schemes are up and running on lots of packaging, but there is a lack of transparency in
the calculations and no international standardization.
16. From offline to online. Brands can no longer hide behind their TV ads or billboard
posters because of the power of online search. Consumers are actively seeking
information about the brands with which they interact. It is increasingly important for
brand image to match company behaviour. After all, 81 percent of UK consumers place
more importance on what companies do than what they say. There is a positive
correlation between transparency and trust.
17. From environmental sustainability to embedded sustainability. The UN
Development and Happiness Index, and the NEF Happy Planet Index integrate human
well-being and environmental impact. The credibility of these indices will continue to
increase. As awareness increases about the intertwined relationship between the
environment and well-being, the public will rapidly demand environmental action.
18. From company claims to external verification. About 64 percent of consumers
want third-party verification of green claims. Some unusual partnerships are already
developing between NGO’s and large organisations—McDonald’s and Greenpeace,
Coca-Cola and WWF, and Vodafone Greece and Greenpeace. As this trend continues,
there needs to be a balance between credibility and values for both the company and the
NGO to retain the trust of consumers.
19. From one renewable success to another. Patents in wind, fuel cells, hydroelectric,
tidal and geothermal were up in 2008 over 2007. In contrast, solar, hybrid/electric vehicle
and biomass/biofuel energy patents fell slightly in 2008. In 2009, it will be interesting to
see which renewable energy sources will continue to develop new technology.
20. From bins to bucks. People are opting to reuse, resell, donate or recycle old goods.
Millions sell used goods on Ebay, which has recently launched “green team” and “world
of good” websites to help users buy, sell and think green. We are beginning to see end
use considered in the design stage of the products we buy. Manufacturers are reusing
parts of returned products, essentially accomplishing two things: repurposing the
materials and holistically extending the life of the product. This is an environmentalists’
dream that will hopefully spread across the business world.
Source: Living Green Magazine
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Growstones and Coco Coir: Perfect Together
Winter means more indoor growing. We’d like to share with you one of our secret recipes
for happy, super healthy plants during those gloomy daylight-savings days.
A Coco-Growstones Mix!
Here are the top advantages of this potent blend:
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Increased aeration and drainage
Allows for more frequent feedings without the risk of over watering
Uniform air and water distribution
Improved root distribution
Avoid compaction and root rot
Environmentally-conscious blend
So why does a Coco-Growstone Blend offer so many benefits above and beyond just pure
coco coir? Because while coco is great, it holds loads of water and as a result can be
easily over-irrigated. It can compact around the roots, leading to lower than desired
aeration/oxygen levels of roots, which in turn can lead to root rot problems.
Growstones, on the other hand, are drier, highly porous and rigid, so even when they are
saturated with water, they are filled with air.
By combining coco coir with Growstones, the mixture is “opened up”, allowing for more
air movement and better drainage. The blend is a drier mix than 100% coco, so more
frequent irrigation may be needed, but at smaller volumes each time. This means that
water consumption remains the same each day, but feeding frequency can be increased.
In itself, this is a very important benefit for plant production: As the number of feedings
per day increases, fresh nutrients can also be provided more frequently, with the potential
for extra production.
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With the addition of Growstones to coco coir, you can increase feedings without the risk
of over watering or root rot. And don’t forget that both Growstones and coco coir are
environmentally friendly products, which makes this blend even more satisfying. So why
not whip up a batch of Coco-Growstones Mix and spend less time worrying about your
soil mixture and more time watching your plants become bigger, stronger and healthier?
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Silica for Happy, Healthier Plants
Silica.
It is the second most abundant element in the earth’s crust and is a major constituent of
plant tissue. However silica can’t be used by plants in just any form. Silica is essentially
sand, which is not soluble in water. So first it must be converted into the soluble silica
acid, which can only happen in the presence of moisture and the right acidity conditions
in the grow medium. This soluble solution is then in a form that a plant can uptake
through its roots and transport it to the stem, leaves and cell wall.
Although Silica has been used for centuries to prevent disease in agriculture (historically
in the form of horsetail extracts), we are only beginning to gain a detailed understanding
of the process and mechanisms at work and of its roles in plant physiology and health.
What we do know, though, is that without silica plants wouldn’t be as strong. They would
wilt more easily. Their leaves would not have the toughness to widen and open, and
capture enough light to photosynthesize efficiently. For hydroponically grown plants, the
beneficial affects of adequate silica are tremendous:
• Thicker leaf cuticles helps reduce powdery mildew, fungus, and insects (like spider
mites and leaf miners) by making it difficult to penetrate the leaf surface causing harm to
the plant.
• Protection from plant stresses such as heat and drought
• Promotes better harvesting of light for faster growth
• Plants can better withstand temperature extremes
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• Strengthens the plant stems allowing them to support heavier fruits & flowers (less
trellising)
• Thicker cell walls on fruits and flowers = stay fresh longer, shelf life, etc.
• Overall increased growth in some plants
• Triggers natural defense mechanisms within the plant
• Helps to alleviate abiotic toxicities accumulated within the plant
Fortunate for us (and for you) silica is released from Growstone in a form plants can
benefit from called Monosilicic acid. In fact, a recent trial study at the Applied Plant
Research Lab at the University of Wageningen found some very positive affects of using
Growstone as a growing medium rather than Rockwool (a perlite-like medium). The
cucumber plants grown in Growstone were harvestable two days earlier than those in the
Rockwool and exbitited much fewer downward curled leaves! Growstone provides a
drier root zone, a requirement for many crops such as cucumbers, and the plant growth
benefited from the usable silica found in the medium. Indeed, Dutch cucumber growers
that visited the trial preferred Growstone over Rockwool in part due in part to its ease of
use in various container systems, its high steer-ability, and its capacity to be steam
sterilized.
Perhap’s most exciting, the Growstone plants had a much higher resistance to soil fungi
such as Pythium. Only one plant succumbed to it, while 15 of those plants grown in
Rockwool were infected and had to be removed. Past studies at UC Davis and the USDA
have shown beneficial effects from adding potassium silicate to the fertilization regime.
Because Growstone already contains silica in a form usable by plants, your plants have
this built-in protection and growth promoter available right in the medium—without
needing to add anything extra!
And as always, Growstone is the environmentally sustainable choice.
So be a plant doctor and make sure you are giving your crops the silica they need to stay
healthy. Are you?
Want more informative articles and “how’s to” on Growstone?
Visit http://www.growstone.com/blog/
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Why Roots Love Growstones
By Paula Costa, PhD
The great advantage of porous media is its ability to provide simultaneously sufficient
levels of oxygen and water to the roots. Water is mainly held in the small pore space of
the medium while rapid drainage and air entry depends on the presence of large pores. So
a good distribution of small and large pores is essential for a good growing medium.
Growstones highly porous and uneven shaped aggregates provide just that – a balanced
combination of small pores inside each aggregate and large pore spaces between
aggregates. This determines Growstones capacity to store water, air, and the ability to
provide them to the plants.
But what’s truly unique about Growstones is the combination of pore size distribution
and pore interconnectivity. Pore interconnectivity results in a large surface area available
for roots to grow in and around. While larger pores between aggregates, assure rapid
drainage and air exchanges, which guarantees oxygen is rapidly dissolved in the water
and supplied to the roots, small pores are filled with fresh air and covered by a film of
oxygen-saturated water. As a result, after irrigation each pore acts as a ‘micro NFT
system’. The combination of small and large pore spaces creates an ideal environment for
roots, microorganisms, and worms to thrive, full of oxygen-rich water, and nutrients.
Growstones pore size and connectivity results in good wicking ability. Growstones
absorb and retain moisture 4 inches above the water level. This wicking ability has
multiple advantages, all associated with creating a constant moist and highly aerated
environment for roots above the water level. These conditions promote continuous
development of hairy roots, which considerably increase the absorption area of the root
system.
Growstones wicking ability also has practical implications on growing. With Growstones,
in flood-drain tables the water level need only to be raised up to 2 to 3 inches below the
surface of the medium. The upper layer of Growstones will keep moist and filled with air.
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This eliminates the possibility of excess moisture at the surface of the medium reducing
chances for fungus gnat infestations and algae growth.
Growstones pore size and interconnectivity also facilitates horizontal water diffusion
leading to uniform moisture distribution, which in turn induces uniform root growth
allowing you to take advantage of the entire volume of growing medium you paid for.
From the growing management point of view, Growstones drier nature in comparison to
other growing media has multiple advantages. It makes it easier to change root zone
nutrients, pH and moisture levels as quickly as desired. As a result, with Growstone it is
easy to transition your plants from vegetative to bloom. Being drier, also allows taking
advantage of frequent feedings with no risk of over-watering or root rot, and it reduces
plant’s susceptibility to Pythium and other fungal diseases.
Finally, because Growstones are made from recycled glass, its surface leaches out silica
in a form roots can uptake – monosilicic acid (H4SiO4). Plants that accumulate silica
have higher resistance to stresses such as drought, salinity heavy metals, and pathogens.
In summary, with Growstones, roots have a larger available surface area, which retains
water and loads of aeration at container capacity. Its unique pore structure promotes the
growth hairy roots, assures uniform root growth through the entire medium, easy
drainage, high leaching effect compared to other less clean substrates, leaving fewer
residues behind. Its dry nature makes it easier to control moisture and nutrient levels, and
to change them as quickly as desired making it easy to transition between development
stages. It also reduces susceptibility to fungal diseases. For all these reasons, Growtones
roots are not just healthier. They are healthier longer.
Root for Growstone on Facebook!
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How to Plant Seedlings in Growstones for
Hydroponic Growing
by Paula Costa, PhD
Growstone Consultant for R&D Applications
Start Up
Most vegetable growers start growing from seed. Other growers either start with seeds or
rooted clones. Both have advantages and disadvantages, so for these growers the decision
depends on personal preference, cost, growing space, crop risk and turn around time. This
article will focus on starting up from seeds.
Seeds and Germination
When growing from seed, the use of certified seeds is recommended. Certification
guarantees the genetic identity of the seed, i.e. seed can be traced back to the original
seed developed by the breeder. It also guarantees that the seed in the bag is true to the
label. Finally, certified seeds are grown and processed to meet certain quality standards,
which include purity of clean seed relative to chaff and dirt, high germination rates, and a
minimum of other plant and weed seeds in the mix.
There are multiple options and ready-to-use systems for seed germination. No matter
what particular system you choose, it has to follow simple basic rules for successful
germination: A soft substrate with good water retention and aeration, and an ability to
drain water away from the seeds keeping just enough moisture in the substrate. Ideally,
the system should also allow maintaining a reasonable relative humidity of the air around
the germinated seedlings and increasing the substrate temperature.
One of the best and simplest systems for successful seed germination is to use a
germination tray with multiple small cells on top of a sub-surface irrigation tray. The
cells on the germination tray hold the substrate where seeds will be placed and germinate
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(germination plugs). It needs to have drainage holes at the bottom of each cell to allow
for drainage. The sub-surface irrigation tray does not have any holes, so it holds the water
added during the germination and growing phase of seedlings. This tray should fit snug
below and around the germination tray.
To increase temperature of the substrate, which will accelerate the germination process
and seedling development, there are ‘heat mats’ that can be placed underneath the subsurface irrigation tray. After germination, to increase relative humidity around the
seedlings, you can use a ‘humidity dome’ that fits tight on top of the germination tray.
If/when the relative humidity or air temperature is too high or too low, simply adjust the
openings in the dome. Both trays, ’humidity dome’ and ‘heat matt’ are available in most
retail hydroponic stores and some garden centers with an hydroponic section.
You can opt for a ready to use germination system, which cells in the tray come already
filled with a germination substrate, or opt to buy the parts (trays, substrate, dome, heat
matt) and do it yourself.
Below are the steps to follow in the second case.
1. Fill the cells with a soft substrate, such as a peat base mix, coco coir, foam plugs,
or stone wool. These will be your germination plugs.
2. Thoroughly soak the substrate and let drain before placing it on top of the subsurface irrigation tray in order to avoid excess water content in the substrate.
Before placing your seeds in the plugs, make sure the substrate is moist to touch,
but not soaking wet.
3. Carefully place one to two seeds in the center of each plug. If your seeds are too
small (such as tomato seeds), use a wet tooth pick to grab and drop the seeds at
the center of the plug.
4. Once all plugs have seeds, cover the tray with the ‘humidity dome’, or with a thin
layer of vermiculite and keep it in a dark space until germination occurs.
5. Whenever the substrate feels dry to touch, add a thin layer of water to the subsurface irrigation tray and watch if more water is necessary to moisten all the
plugs homogenously until the substrate feels slightly moist to touch.
6. After germination (when cotyledons emerge), place the tray under grow lights or
bring to partial sun.
7. Start irrigating with a diluted nutrient solution for seedlings.
8. Ideally, at this point, the ‘humidity dome’ should be placed to cover the seedlings
in order to keep a high relative humidity. Alternatively, you can build a clear
plastic cover over the seedlings without touching the plants, for the same effect,
making sure to make some holes to facilitate air exchanges. If using the ‘humidity
dome’, adjust the openings to reduce/increase the relative humidity and
temperature.
9. When true leaves are visible, go over the tray and remove by hand the seedlings
that look less vigorous from each plug. This will allow keeping only the most
vigorous plants.
10. Once healthy roots are visible from bottom and side of the plugs, it is time to
transfer the seedlings into your hydroponic system filled with Growstones.
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For best results, it is recommended to plant onto Growstones which have been prepared
as described on our February 9 blog post: How to Prepare Growstones for Hydroponic
Use.
Planting into Growstones
Keep in mind that young roots of seedlings are very fragile and should be handled gently.
Whatever your hydroponic system may be, follow these simple steps for planting in
Growstones:
1. Start by filling your growing container with Growstones halfway up. The size of
the container should be proportional to the expected final size of the plant. For
example, tomato plants develop a dense root system to sustain a lush and
relatively large plant, thus a container size between 15 and 25 gallons is
recommended to avoid root bound.
2. Gently detach the plugs (substrate + seedling) from the tray, one plug at a time,
keeping the substrate attached to the roots.
3. Place the plugs at the center of your container above the Growstones. If the
container is large and wide enough, you can place two plugs per container.
4. Fill the rest of the container around the plug with Growstones up to 1” to 2”
below the edge of the container.
5. Irrigate immediately after planting to promote contact between the new substrate
and roots.
Note: For Ebb-Flow systems, due to Growstones light weight, it is important to use
completely wet Growstones in order to keep pots from tipping sideways during initial
water Ebb-flow cycles when plants are very small. This is not an issue on all other
hydroponic systems.
Irrigation schedule & implications on growing
The irrigation schedule and the physical properties of the substrate are the most important
factors determining how plants will develop. There are no strict recipes for irrigation
when growing hydroponically. The best irrigation schedule should be determined by your
crop and growing goal: Are you growing flowers and fruits, or leaves and other
vegetative parts?
As a general rule, an irrigation schedule which allows for a certain dryness of the root
zone between irrigations and especially during the night period and early morning/light
period, results in a earlier onset of flower development, and in some cases with more
flowers. This is due to the fact that water stress is a trigger for reproductive plant
development. This means the plant shifts more of its energy (photoassimilates) into
reproductive parts such as flowers to guarantee seed production and thus the survival of
future generations. With a high irrigation frequency and root zone constantly moist, the
opposite occurs, i.e. more vegetative parts, such as leaves and stems are preferentially
developed compared to flowers.
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The control over the moisture content of the root zone is instrumental to grow a good
crop. This is achieved by the right combination between substrate with respect to aeration
and drainage, and irrigation schedule.
Most important in any growing medium is the air in the medium after drainage. Plant
roots require air (particularly oxygen) for growth process respiration. However, it is
important to note that plants vary widely in aeration requirements (percentage of air
space after irrigation water has drained away). For example, while the aeration
requirements of azaleas, ferns, and epiphytic orchids are very high; they are very low for
plants like carnations, roses, geraniums, palms, strelitzia, and grass (Cornell Cooperative
Extension, Container Growing Mediums and Amending Garden Soil, 2000).
An ideal substrate has small and large pores (micro pores and macro pores). When the
substrate is irrigated, water is held in the micro pores but quickly drains through the
macro pores, allowing air to flow through the soil, which brings oxygen to the roots and
removes carbon dioxide from the root zone.
Typically these substrates are characterized by fast drainage, a reasonable reservoir of
water after drainage, and most importantly, a high percentage of air spaces after drainage.
They also allow for rapid changes in the concentration of the nutrient solution (EC or
TDS), as it is easier to reduce/increase concentration of nutrients available to the roots in
substrates which water content can change fast.
These characteristics are present in low bulk density, highly porous substrates such as
Growstones.
Thus, if the focus of growing is to produce a leafy crop (vegetative part), the most
suitable irrigation schedule should be based on irrigations frequent enough to keep
Growstones moist to touch at 1” to 2” below the surface between irrigations, and irrigate
long enough to see some drainage at the bottom of pot (when applicable) each time you
irrigate. Initially, with small plants, 2 to 3 irrigations per day could be sufficient. As plant
grows and develops more and larger leaves, the irrigation frequency/duration needs to be
increased/adjusted in order to accomplish the same goal and satisfy an increasing
transpiration surface (larger area and number of leaves).
If the focus is to produce flowers or fruits, the irrigation schedule should allow for
periods of root zone dryness. However, if a drier root zone can be beneficial in achieving
the goal of more and faster flowering, it can also be dangerous if plants are not closely
monitored. Make sure to observe your plants and that irrigation occurs preferentially
before any visible signs of wilting.
Some plants do seem to benefit from drying a bit further and respond well to irrigation
even after wilting is visible. Make sure your plant falls under this category before setting
your irrigation schedule.
Irrigation Equipment
Even before planting, it is important to start thinking about irrigation. Make sure you
have all the equipment necessary to control the irrigation schedule (frequency and
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duration), and monitor nutrient solution pH and concentration (electric conductivity, EC
or Total dissolved solutes, TDS).
Unless you are irrigating continuously, you will need an irrigation timer to set up an
irrigation schedule. There are multiple easy to use irrigation timers available in the
market.
In order to monitor the pH and concentration of your nutrient solution (EC or TDS), you
will need to purchase a reliable pH and EC or TDS meter. There are several brands
available in the market today.
Hydroponic nutrients are sold as concentrated solutions and have to be added to your
hydroponic system water at a certain ratio to achieve the adequate concentration. Ideally,
the concentration of nutrients in solution should fall between an EC of 2.0 and 3.0 mS/cm
(corresponding to a TDS around 1000 to 1500 parts per million, ppm according to NaCl
conversion), and pH between 5.5 and 6.5.
Often, the meters will be able to read a wide range of values, so it is important to choose
a pH, EC or TDS meter which reading range falls within the normal pH and EC or TDS
range appropriate for your nutrient solution. Due to calibration and maintenance issues,
separate meters for pH and EC or TDS are recommended, instead of the pH and EC or
TDS combo.
You will also have to purchase the respective calibrating solutions and buffer to keep the
pH and EC probes in good working conditions and get meaningful readings.
Maintenance
Daily – Monitor pH and EC or TDS of the nutrient solution.
As needed – Make sure the levels of the nutrient solution in the reservoir tank are kept
constant or at least within range, by adding fresh water as needed for a period of time.
Every two weeks – Flush the system and make fresh nutrient solution. If there are no
signs of diseases, it is a good idea to discard the old nutrient solution around your garden
to take advantage of nutrients still present in the nutrient solution.
Each time you make fresh nutrient solution, let the system operate for a few minutes in
order to completely mix water and nutrients before adjusting pH, as the final pH of the
nutrient solution is affected by the nutrients used.
Reusing Growstones
Growstones can be used multiple times as they keep their physical integrity through time.
All it requires is a vigorous shake to remove most of the roots, and placing the
Growstones back in the system. As with any other media, sterilization of used media
between crops is recommended. This can be accomplished either by flushing the
hydroponic system and used Growstones with diluted beach solution. When available,
steam sterilization is also a great option.
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Share your fruits!
Send us your photos of growing with Growstones and we’ll share with our ever growing
community. Good fruits and vegetable growing with Growstones!
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Advantages of Growstones Over Hydroton
by Paula Costa, Growstone Consultant for R&D Applications
Growers have had a love hate relationship with Hydroton for years. Now there’s finally a
choice. Besides the clear advantage of providing a higher level of aeration than Hydroton,
Growstones hold more water, have no fines, and release silica over time in a form plant
roots can uptake.
Here are some of the advantages of Growstones aggregates over Hydroton based on
actual physical characteristics of both substrates.
1. Higher air-filled porosity.
At field capacity (i.e. after irrigation water has drained away), Hydroton air-filled
porosity is about 42%, while Growstones hydroponic media is 48% by volume. This
corresponds to at least 12% higher aeration in Growstones than Hydroton. The
importance of high porosity in hydroponic growing cannot be undermined. Ideal
substrates have small and large pore spaces. When the substrate is irrigated, water is held
in the small pores but quickly drains through the large pores, allowing fresh air to flow
through the soil, bringing oxygen to the roots and removing carbon dioxide from the root
zone.
2. Significantly higher water holding capacity.
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Hydroton is characterized by a very low water holding capacity: 9.6% compared with
29.4% by volume for Growstones hydroponic media. This corresponds to 78% higher
moisture content after drainage.
The significance of points 1 and 2 is that Growstones much higher water holding
capacity, is not achieved at the expenses of air-filled porosity, quite the opposite, as
mentioned in point 1. This is explained by Growstones very low bulk density and
corresponding high air-filled porosity.
3. Significantly lower bulk density (lightweight).
Growstones are very lightweight with a bulk density of 0.20 g/cc; while Hydroton bulk
density is 0.40 g/cc. This explains Hydroton’s significantly lower water retention since its
porosity depends solely on the large pores between Hydroton pellets, which enhances
drainage and aeration, but does little for moisture retention. Hydroton high bulk density
also has important implications on shipping costs from Germany where it is
manufactured.
4. Highly porous substrate with no fines (dust).
Growstones and Hydroton are both fast draining well-aerated hydroponic media. The
advantage of Growstones hydroponic media is that it contains almost no fines, oppose to
Hydroton characteristic clay fines, which leach out and tend to accumulate at the bottom
of the nutrient reservoir.
5. Growstones release silica in a form plants can uptake.
Growstones are made of 98% vitreous soda lime glass. Therefore, Growstones aggregates
contain silica, which leaches out through time into the nutrient solution in a form easily
uptake by plant roots.
As such, Growstones provide a higher level of aeration/oxygen diffusion, with the added
advantage of holding a significantly higher amount of water, absence of fines, and release
silica over time in a form plant roots can uptake.
Also relevant is the fact that Growstones are made from recycled glass, right here in the
USA. Besides the obvious advantages of choosing national products, the Growstones
choice significantly reduces waste glass in landfills, clay mining and carbon miles
associated with long distance shipping from Germany where Hydroton is manufactured.
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The Importance of Aeration to Soil
The better your soil breathes, the more it benefits your plant’s growth. Everything in
nature needs oxygen to thrive. Dense, compacted, heavy soils tend to negatively impact
oxygen flow. That’s why your soil needs aeration to allow oxygen and vital nutrients to
efficiently reach your plants roots. The harder a plant works to accomplish this, the less
energy it has for growth and yield.
Aeration is also important for all the following reasons:
Plant and Root Growth: Inadequate oxygen in soil either retards plant growth or causes it
to cease completely. Abnormally shaped roots are common in compacted or poorly
aerated soil.
Microorganism Population and Activity: Beneficial microorganisms also need air for
respiration and metabolism. Important microbial activity such as decomposition of
organic matter, nitrification and other vital activities depend on the oxygen present in
soil.
Growth of Toxins: Poor aeration results in the development of toxins in your soil.
Water and Nutrient Absorption: Oxygen deficiencies have been found to check nutrient
and water absorption in plants.
Disease Development: Insufficient aeration leads to the development of plant diseases.
No matter what else you do, give your soil a breath of fresh air by regular aeration. Check
out our Super Soil Aerator. It supplies superior air and water retention ratios for superior
plants.
Got a aeration tip you want to share?
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Lose Your Fines
When it comes to growing and using products to aerate your soil, it’s all about the dust.
As grow mediums break down in shipment or through handling, they tend to breakdown
into dust, which are called “fines”.
A recent study, conducted at the University of Arkansas Plant Sciences Department,
looked at the differences in fines between horticultural grade perlite and Growstone. The
tests were done over the course of a month using a number of containers and a variety of
irrigation methods, from hand held watering to drip tubes. They found some pretty
amazing results:
1. Horticultural perlite contained 52% more fines than Growstone
So right out of the bag, perlite is already a dustier medium than Growstone. This means
you are paying for unusable product from the get-go.
2. When used to prepare sphagnum peat-based mixes, those made with
horticultural perlite lost 14% more aggregates to fines compared to those made with
Growstone.
This means that when you are mixing up a batch of grow medium, perlite is more likely
to disintegrate into fines than Growstone, reducing your quantity of valuable aggregates.
3. Perlite fines are lighter weight than Growstone fines, which means that they often
floated out of the containers with the drainage water or remained sitting in the top
layer of grow medium.
Contrary to perlite, Growstone does not tend to float to the top of your pot and wash
away when irrigated. Because of Growstone’s courser texture, Growstone tends to grab
on to the peat or coir and not “float” up to the top of the pot and eventually wash away.
All of these results are important for container gardeners, soil blenders, those with
elaborate filter and irrigation systems, and anyone who needs to reuse and conserve their
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grow medium. Make the smart choice and switch to Growstone. Isn’t it time you lose the
fines?
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