Media publicity is something you want to generate. It's free and it gets you the type of exposure most people pay a lot of money for. The key with media publicity is that you can use it for your own publicity over and over again.
Here are some ways to become savvy around reporters that will maximize your opportunities for media coverage.
To garner media publicity you have to be perceived as an expert source. Host as many seminars and get on as many committees as possible.
When the media come to you about a story try to distinguish yourself by thinking of a unique hook or angle. This way your ideas are more likely to get quoted and you get the media publicity over other potential experts.
If you want media attention then you need to treat the media well. Always return phone calls and emails ASAP. The media publicity often goes to the first two out of 10 experts a reporter calls.
Befriend the reporters that cover your beat. Media publicity is sought after so make yourself the go-to guy for one or two reporters.
The media are always looking for interesting stories. Don't just pitch them on you, you, you. If you think of something that is newsworthy you can almost guarantee media publicity.
To get media publicity you have to be creative. Feed the media tales from the trenches and allow them an insiders look at the IT world.
Regardless of how you get media publicity you have to remember not to get frustrated if the media publicity you generate does not attract immediate attention. Even if you manage to land the front page after months of pitching your media publicity idea, you're phone won't necessarily start ringing off the hook. You might get a few inquiries and some congratulatory calls but the media publicity is more about building your credibility than converting sales.
Use your media publicly wisely and translate it into your business' marketing collateral. This is where the real power of media publicity comes into play. You can use it over and over again; long after the newspaper is thrown away or the newscast is finished.
Bottom Line on Media Publicity Build relationships with reporters and make their job easier by pitching them ideas that will garner you media publicity. You will be the big winner in the long run.
Copyright MMI-MMVII, Small Business Computer Consulting .com. All Worldwide Rights Reserved. {Attention Publishers: Live hyperlink in author resource box required for copyright compliance}
Wednesday, March 26, 2008
Communications And Information Sources Through Media
You thought of it, you researched it, you wrote it. So you own your story. At least you do until you send it to the media.
At that point, they are free to do whatever they want with the information you gave them.
Your job from then on: control and communicate it to the maximum. Offer new information if you find it. Steer them to resources that may help them flesh out the story. Assure them that you will be available for follow-ups, day or night.
But they own the media outlet. Their job: creating the story as it will appear in their newspaper, magazine or over the airwaves.
Unless you are authoring an article to appear under your own byline, don’t expect – or request – approval rights, an advance peek, or any changes. They may never call again if you do.
Occasionally, a reporter will offer to show you the story before it runs. That’s different. It’s usually because they want to check facts, or ensure that they have quoted you correctly.
Always say yes if they initiate this offer. Even if you have 12 meetings tomorrow morning, and are undergoing surgery after lunch. This is a chance to make yourself sound as knowledgeable and intelligent as possible to the thousands of potential clients that will read the article.
At that point, they are free to do whatever they want with the information you gave them.
Your job from then on: control and communicate it to the maximum. Offer new information if you find it. Steer them to resources that may help them flesh out the story. Assure them that you will be available for follow-ups, day or night.
But they own the media outlet. Their job: creating the story as it will appear in their newspaper, magazine or over the airwaves.
Unless you are authoring an article to appear under your own byline, don’t expect – or request – approval rights, an advance peek, or any changes. They may never call again if you do.
Occasionally, a reporter will offer to show you the story before it runs. That’s different. It’s usually because they want to check facts, or ensure that they have quoted you correctly.
Always say yes if they initiate this offer. Even if you have 12 meetings tomorrow morning, and are undergoing surgery after lunch. This is a chance to make yourself sound as knowledgeable and intelligent as possible to the thousands of potential clients that will read the article.
Tuesday, March 25, 2008
Little Facts
Little known facts can be just interesting. Here are some of those: A typical lightning bolt is two to four inches wide and two miles long; A month that starts with a Sunday will have a Friday the 13th in it; Easter is the first Sunday after the first full moon after March 21; Close to 50% of all bank robberies take place on Friday.
Do you know the furthest point on Earth from the center? It's the peak of Mount Chimborazo, in Ecuador, near the Equator. The Earth bulges at the equator, making Mount Chimborazo even further out there than Everest.
Then there are the little known facts that are funny. These include, for example, silly laws that are still on the books. Here are some of those: By law, people in Vermont must take at least one bath a week; In Oklahoma, dogs need a permit signed by the mayor in order to congregate on private property in groups of three or more; In Roanoke, VA, it’s against the law to advertise on tombstones; It’s illegal to put coins in your ears in Hawaii.
"Odor Judger" is an actual job title, and job description. So do you want to smell armpits all day to help make effective deodorants? I'm not sure why somebody other than some strange fetishist would want this job.
Useful Little Known Facts
Little known does not mean not useful. There are many things most people don't know that can be extremely useful. A few of these follow.
When an item can't be removed from your credit report, you have the right to add a 100-word explanation to it, permanently. All who receive the report will see your explanation. If, for example, you had an argument with a doctor over a charge, you can explain the details.
You can get free x-rays. Some dental schools will x-ray your mouth for free, if you have the patience to sit there while the instructor coaches the student through the process. You then get your x-rays to take to the dentist.
Thre are still towns with nice houses you can buy for less than $30,000. As of January, 2006, these include Altoona, Pennsylvania, Anaconda Montana, Hot Springs, Arkansas, and Independence, Kansas. More are listed on the web site: Houses Under Fifty Thousand .com.
Buy two separate plane tickets to save hundreds. It cost $1750 to fly round trip from Traverse City, Michigan to Quito, Ecuador. That was the cheapest fare we found on any website. However, it was only $299 round-trip to Miami, and $405 round-trip from Miami to Quito. $704 total! Save over $1000 by buying two separate tickets.
You can't fold a dollar bill in half eight times, doubling it each time. In fact, try it even with a large piece of paper. It can't be done. You can win a bar bet with this fact, so I'll classify this one among the interesting, funny AND useful little known facts.
Do you know the furthest point on Earth from the center? It's the peak of Mount Chimborazo, in Ecuador, near the Equator. The Earth bulges at the equator, making Mount Chimborazo even further out there than Everest.
Then there are the little known facts that are funny. These include, for example, silly laws that are still on the books. Here are some of those: By law, people in Vermont must take at least one bath a week; In Oklahoma, dogs need a permit signed by the mayor in order to congregate on private property in groups of three or more; In Roanoke, VA, it’s against the law to advertise on tombstones; It’s illegal to put coins in your ears in Hawaii.
"Odor Judger" is an actual job title, and job description. So do you want to smell armpits all day to help make effective deodorants? I'm not sure why somebody other than some strange fetishist would want this job.
Useful Little Known Facts
Little known does not mean not useful. There are many things most people don't know that can be extremely useful. A few of these follow.
When an item can't be removed from your credit report, you have the right to add a 100-word explanation to it, permanently. All who receive the report will see your explanation. If, for example, you had an argument with a doctor over a charge, you can explain the details.
You can get free x-rays. Some dental schools will x-ray your mouth for free, if you have the patience to sit there while the instructor coaches the student through the process. You then get your x-rays to take to the dentist.
Thre are still towns with nice houses you can buy for less than $30,000. As of January, 2006, these include Altoona, Pennsylvania, Anaconda Montana, Hot Springs, Arkansas, and Independence, Kansas. More are listed on the web site: Houses Under Fifty Thousand .com.
Buy two separate plane tickets to save hundreds. It cost $1750 to fly round trip from Traverse City, Michigan to Quito, Ecuador. That was the cheapest fare we found on any website. However, it was only $299 round-trip to Miami, and $405 round-trip from Miami to Quito. $704 total! Save over $1000 by buying two separate tickets.
You can't fold a dollar bill in half eight times, doubling it each time. In fact, try it even with a large piece of paper. It can't be done. You can win a bar bet with this fact, so I'll classify this one among the interesting, funny AND useful little known facts.
Monday, March 24, 2008
7 Secrets of Great Media Release
Recently I rewrote and edited my last Media Motivators article on the McEddie "Everywhere" McGuire personal brand and turned it into a media release.
It generated two high profile radio interviews on ABC and commercial radio and a Google search on the words "Eddie McGuire" positioned my story on the first page at number 10 out of a possible 3.2 million mentions.
It also prompted one news editor to contact me and ask if I could write a column for his influential, high-profile and award-winning newspaper.
So how did I do it? More importantly, how can you turn your expert knowledge into a news release that gains you tens of thousands of dollars worth of media coverage for free?
And what are the secrets of writing media releases that get used instead of deleted and ranked highly in Google?
This is a question critical to gaining ongoing media coverage in a consistent way for any organisation or individual.
How to write a news release that generates free publicity is a great skill to have. The good news it is a learned skill!
This article covers media release writing in detail - the 7 secrets of writing a great news release.
1. Strong News Value
Your media release must have a strong news value and not be trying to sell something or be blatant advertising. The media will see through this.
Conflict, drama, currency, relevance, proximity, prominence, and timeliness are the strongest news value.
Ask: what is new about what we're doing?
2. A Well Written Headline
A headline must grab the attention of the editor or reporter.
3. A Well Written Lead Paragraph
A lead paragraph must continue to hold the attention of the editor or reporter and summarise what the story is about.
4.Quotable Quotes
Quotable quotes add credibility and human interest to a media release. They are the flesh that goes on the facts or bare bones of the story. They must be memorable and well crafted.
Take this quote from a famous athlete who had just come out of retirement, "I'm bored, I'm broke and I'm back!".
Nice - simple, memorable and direct. Plus the media love it because of its honesty, structure and rhyming nature, especially the alliteration with all the first words starting with the letter 'b'.
5. Clarity In Writing Style
Clear writing is a sign of clear thinking. Don't try and put the whole story across with every detail. Remember, the aim is to get the media interested in the story and then call for more detail.
A media release is not the same as an article, promotional brochure or detailed announcement to the Australian Stock Exchange!
6. Strong Call To Action
Your media release must end with a call to action. What is it you want people to do after reading or hearing your message?
Invest in your stock, buy your book or vote for you!
7. Comprehensive Contact Details
A news release should always contain current contact details for the media to follow-up.
At a minimum these are landline, mobile, web and email.
Thomas Murrell MBA CSP is an international business speaker, consultant and award-winning broadcaster. Media Motivators is his regular electronic magazine read by 7,000 professionals in 15 different countries.
It generated two high profile radio interviews on ABC and commercial radio and a Google search on the words "Eddie McGuire" positioned my story on the first page at number 10 out of a possible 3.2 million mentions.
It also prompted one news editor to contact me and ask if I could write a column for his influential, high-profile and award-winning newspaper.
So how did I do it? More importantly, how can you turn your expert knowledge into a news release that gains you tens of thousands of dollars worth of media coverage for free?
And what are the secrets of writing media releases that get used instead of deleted and ranked highly in Google?
This is a question critical to gaining ongoing media coverage in a consistent way for any organisation or individual.
How to write a news release that generates free publicity is a great skill to have. The good news it is a learned skill!
This article covers media release writing in detail - the 7 secrets of writing a great news release.
1. Strong News Value
Your media release must have a strong news value and not be trying to sell something or be blatant advertising. The media will see through this.
Conflict, drama, currency, relevance, proximity, prominence, and timeliness are the strongest news value.
Ask: what is new about what we're doing?
2. A Well Written Headline
A headline must grab the attention of the editor or reporter.
3. A Well Written Lead Paragraph
A lead paragraph must continue to hold the attention of the editor or reporter and summarise what the story is about.
4.Quotable Quotes
Quotable quotes add credibility and human interest to a media release. They are the flesh that goes on the facts or bare bones of the story. They must be memorable and well crafted.
Take this quote from a famous athlete who had just come out of retirement, "I'm bored, I'm broke and I'm back!".
Nice - simple, memorable and direct. Plus the media love it because of its honesty, structure and rhyming nature, especially the alliteration with all the first words starting with the letter 'b'.
5. Clarity In Writing Style
Clear writing is a sign of clear thinking. Don't try and put the whole story across with every detail. Remember, the aim is to get the media interested in the story and then call for more detail.
A media release is not the same as an article, promotional brochure or detailed announcement to the Australian Stock Exchange!
6. Strong Call To Action
Your media release must end with a call to action. What is it you want people to do after reading or hearing your message?
Invest in your stock, buy your book or vote for you!
7. Comprehensive Contact Details
A news release should always contain current contact details for the media to follow-up.
At a minimum these are landline, mobile, web and email.
Thomas Murrell MBA CSP is an international business speaker, consultant and award-winning broadcaster. Media Motivators is his regular electronic magazine read by 7,000 professionals in 15 different countries.
Tuesday, March 4, 2008
Technology Used In Social Media
It is not too often that we Generation Y members can impart wisdom to our superiors with great acceptance. In fact, we have been widely criticized for a lack of work ethic and sense of entitlement. We will be the first to admit, we still have plenty to learn. However, when it comes to the world of new media, we have a keen advantage over our 'elders' and can likely teach them a thing or two. After all, we have been involved with social media for years now. Moreover, we've been doing it for fun.
Social media is taking corporate America by storm. Executives from large and small businesses alike must educate themselves and follow this trend or it is likely they will slowly become more and more obsolete as change-ready firms leave them in their proverbial 'dust.'
As communications professionals it is our job to stay informed on this trend. We must understand and convey the most effective ways to communicate our clients' messages. Until now, new media has been an extension of our social lives. We are able to chat via text in real time using instant messenger or, as we call it, "IM" and we spend hours searching for old friends from across the globe on social networking sites. Who would have imagined that our fun could be repurposed for business life!
Companies worldwide are beginning to use the social networking and video posting sites that we've been using for years (not to mention reading our blogs and vlogs), so it is important to not underestimate the technology involved.
It is also vital not to underestimate the knowledge your younger staff has to offer with regard to the best utilization of new media.
We don't guarantee to be experts and quite frankly, we do not fully understand the capabilities that these emerging technologies can offer, but we would like to share some basic knowledge from a communications perspective.
Social Networking Sites: In the most basic terms, a social networking site connects its members through an online portal. It is parallel to a networking event. Your online profile serves as a virtual business card. It is one of the simplest forms of new media and the first step you should take when adopting a new media strategy.
We suggest you refer to facebook.com, myspace.com or linkedin.com to begin growing your social network. In our opinion facebook.com is more appropriate for top-level executives, where myspace.com serves those individuals more involved in pop-culture that might attract the more unsophisticated side of people's interests. Linkedin.com is newer and more tailored toward business professionals, and is picking up steam.
Video Posting: If you have not heard of YouTube, you have a lot to learn. For our purposes we won't hold it against you (just hire a Gen Y'er immediately following the completion of this article). YouTube is a video posting site where any person in the world can create, edit and post video content to the internet.
You probably wonder why the phenomenon of anyone with a computer and a camera becoming an editor, director and executive producer all in one, really matters to you. "Will it Blend?" is your answer. Directly after hiring your Gen Y'er please Google "Will it blend?" It is the story of Tom Dixon, founder of Blendtec who posted video of himself blending ridiculous things such as iPods and marbles. This video resulted in his blender sales increasing an exponential rate. We guarantee you will find this clip interesting and it might even inspire you to grab your video camera and get filming!
Blogging: Blogs are another very simple, albeit powerful, form of new media. Blogs are an individual's documentation of anything they would like to share with the Internet community. Simply put, a blog is a digital diary with no key.
Some blogs are personal and share life stories: we have a friend with a family in London that posts on a blog two to three times a week to update her family in the States on their pursuits across the ocean.
Some blogs are topic based: as self-proclaimed fashionistas, a large part of our fashion sense is gathered from blogs such as dailycandy and whowhatweardaily, rather than flipping through the pages of the latest InStyle magazine.
Either way you look at it, blogs act as essential sources of information and are an excellent way to quickly reach a broad audience with your message.
As we said before, we are not new media experts. While us Gen Y'ers feel we can boast our knowledge of new media because a lot of this is old hat to us - the truth is, there is still so much we need to learn.
Personal Life versus Professional Life - Where to Draw the Line?: Since social networking sites, uploading photos to the web and watching videos on YouTube for entertainment purposes have come as second nature, we face a dilemma when trying to decipher where our personal life ends and professional life begins on the web.
For example, you can befriend colleagues on Facebook, but there is an awkward, "don't want to share too much" moment. There is a fine line that constantly shifts and it takes true poise to find the appropriate balance between private and public life. This challenge is constantly irking Gen Y.
Technology Behind the Tool: Also, while we can spend hours messaging friends, blogging and sharing videos, we understand what we're doing and the overall benefits, but we don't necessarily understand the technology that goes into making it all happen.
Social media is taking corporate America by storm. Executives from large and small businesses alike must educate themselves and follow this trend or it is likely they will slowly become more and more obsolete as change-ready firms leave them in their proverbial 'dust.'
As communications professionals it is our job to stay informed on this trend. We must understand and convey the most effective ways to communicate our clients' messages. Until now, new media has been an extension of our social lives. We are able to chat via text in real time using instant messenger or, as we call it, "IM" and we spend hours searching for old friends from across the globe on social networking sites. Who would have imagined that our fun could be repurposed for business life!
Companies worldwide are beginning to use the social networking and video posting sites that we've been using for years (not to mention reading our blogs and vlogs), so it is important to not underestimate the technology involved.
It is also vital not to underestimate the knowledge your younger staff has to offer with regard to the best utilization of new media.
We don't guarantee to be experts and quite frankly, we do not fully understand the capabilities that these emerging technologies can offer, but we would like to share some basic knowledge from a communications perspective.
Social Networking Sites: In the most basic terms, a social networking site connects its members through an online portal. It is parallel to a networking event. Your online profile serves as a virtual business card. It is one of the simplest forms of new media and the first step you should take when adopting a new media strategy.
We suggest you refer to facebook.com, myspace.com or linkedin.com to begin growing your social network. In our opinion facebook.com is more appropriate for top-level executives, where myspace.com serves those individuals more involved in pop-culture that might attract the more unsophisticated side of people's interests. Linkedin.com is newer and more tailored toward business professionals, and is picking up steam.
Video Posting: If you have not heard of YouTube, you have a lot to learn. For our purposes we won't hold it against you (just hire a Gen Y'er immediately following the completion of this article). YouTube is a video posting site where any person in the world can create, edit and post video content to the internet.
You probably wonder why the phenomenon of anyone with a computer and a camera becoming an editor, director and executive producer all in one, really matters to you. "Will it Blend?" is your answer. Directly after hiring your Gen Y'er please Google "Will it blend?" It is the story of Tom Dixon, founder of Blendtec who posted video of himself blending ridiculous things such as iPods and marbles. This video resulted in his blender sales increasing an exponential rate. We guarantee you will find this clip interesting and it might even inspire you to grab your video camera and get filming!
Blogging: Blogs are another very simple, albeit powerful, form of new media. Blogs are an individual's documentation of anything they would like to share with the Internet community. Simply put, a blog is a digital diary with no key.
Some blogs are personal and share life stories: we have a friend with a family in London that posts on a blog two to three times a week to update her family in the States on their pursuits across the ocean.
Some blogs are topic based: as self-proclaimed fashionistas, a large part of our fashion sense is gathered from blogs such as dailycandy and whowhatweardaily, rather than flipping through the pages of the latest InStyle magazine.
Either way you look at it, blogs act as essential sources of information and are an excellent way to quickly reach a broad audience with your message.
As we said before, we are not new media experts. While us Gen Y'ers feel we can boast our knowledge of new media because a lot of this is old hat to us - the truth is, there is still so much we need to learn.
Personal Life versus Professional Life - Where to Draw the Line?: Since social networking sites, uploading photos to the web and watching videos on YouTube for entertainment purposes have come as second nature, we face a dilemma when trying to decipher where our personal life ends and professional life begins on the web.
For example, you can befriend colleagues on Facebook, but there is an awkward, "don't want to share too much" moment. There is a fine line that constantly shifts and it takes true poise to find the appropriate balance between private and public life. This challenge is constantly irking Gen Y.
Technology Behind the Tool: Also, while we can spend hours messaging friends, blogging and sharing videos, we understand what we're doing and the overall benefits, but we don't necessarily understand the technology that goes into making it all happen.
Advantages Of Growing Media For Profit Increase
Container production has been expanding in recent years. Choosing the optimal medium requires special consideration, because it is much more than just an anchor for the plant: it can be crucial to successful crop. Physical and chemical properties of growing media differ from those of soil and container production requires more attentive management.
There are many advantages to using growing media:
* High yields can be achieved on a limited area
* Better control over Irrigation and fertilization
* Easier disinfection
* Recycling of drainage water is possible
* Growing media can be used as an alternative to an inadequate soil (due to drainage problems, salinity etc.)
Of course, there are also disadvantages:
* Nutrient holding capacity is low
* Buffer capacity is low and therefore changes are rapid
In this report we will focus only on the physical properties. The chemical properties will be discussed in a separate report.
What Are The Physical Properties of Good Growing Media?
A balance between air content and available water is one of the most important requirements of good media. Plant roots require air for oxygen supply and gas exchange, and therefore, aeration is critical for optimum plant development. Lack of adequate aeration results in poor plant growth, susceptibility to diseases and nutrient deficiencies. Ideal growing media provide plants with adequate water supply and at the same time contain enough air to allow gas exchange in the root system.
Good growing media are also characterized by high hydraulic conductivity, i.e. ability to transmit water.
Another important property is the medium's weight: it should be light weight for easy and less expensive transport and handling. But it should also be heavy enough to provide physical support to the plant.
Growing Medium And Production System Compatibility
It may be surprising, but in order to choose the best medium, the first thing you should do is consider the production system's specifications. These include: the type of irrigation technique (drippers density and discharge), containers size and containers shape. These factors and the growing medium must be compatible in order to obtain uniform distribution of the irrigation water and effective irrigation.
Porosity and Water holding Capacity
Each growing medium has a characteristic particle size distribution. The spaces (pores) between the solid particles can be filled with either air or water and are referred to as "total porosity".
Each medium contains pores of various sizes. Smaller pores can retain water with more force than larger ones. A pore that is too large cannot hold water against gravity, and empties. The higher the pore is positioned in the container, the smaller it has to be in order to retain water against gravity. At the top of the container, pores which are too large to hold water against gravity are empty. Therefore, the top of the container will always be dryer than the bottom. At the bottom of the container, all pores, including the largest, are filled with water, making the bottom layer saturated.
Water Retention Curves
Labs can accurately measure the water percentage by volume (v/v in %) at given heights of the medium, after saturation and drainage. The height is measured in cm and the data can be graphically presented as a "Water Retention Curve". Some labs refer to the height as "tension in cm".
Containers Size and Shape
We mentioned above that the size and shape of the containers, in which the medium is placed, determine the amount of water that the media hold.
If we fill a few containers of the same volume, but different shapes, with the same medium and irrigate to saturation, the water will reach the same height in each of the containers.
The same water content in % will be measured at each height (according to the water retention curve of this medium). But because of the different shapes, the actual amount of water is different in each container.
This results in different water/air ratio in each container and in different irrigation management.
Irrigation frequency and amount of water applied in each irrigation are determined by the available water content of the medium and by the container shape and size. For example, one irrigation cycle a day is not enough, if the water consumption of the plant is higher than the amount of available water in the container medium.
Hydraulic Conductivity
As the name suggests, hydraulic conductivity is the rate in which a medium transmits water. Hydraulic conductivity of media is not routinely measured in lab tests. Nevertheless, it is extremely important to understand its significance. Hydraulic conductivity is in effect the limiting factor of water uptake by plants in container media, rather than the water quantity in the medium.
When transpiration rate exceeds the hydraulic conductivity of the medium the plant cannot efficiently use the water contained in the medium and might wilt. In materials used for container media, the hydraulic conductivity decreases exponentially as the medium dries. This is because continuity of water is disrupted after the larger pores empty.
Guy Sela is an agronomist and water specialist. In 2005 Guy developed a unique software for fertilizer management that help growers to reach higher and better yields, save time and frustration and increase their profits.
There are many advantages to using growing media:
* High yields can be achieved on a limited area
* Better control over Irrigation and fertilization
* Easier disinfection
* Recycling of drainage water is possible
* Growing media can be used as an alternative to an inadequate soil (due to drainage problems, salinity etc.)
Of course, there are also disadvantages:
* Nutrient holding capacity is low
* Buffer capacity is low and therefore changes are rapid
In this report we will focus only on the physical properties. The chemical properties will be discussed in a separate report.
What Are The Physical Properties of Good Growing Media?
A balance between air content and available water is one of the most important requirements of good media. Plant roots require air for oxygen supply and gas exchange, and therefore, aeration is critical for optimum plant development. Lack of adequate aeration results in poor plant growth, susceptibility to diseases and nutrient deficiencies. Ideal growing media provide plants with adequate water supply and at the same time contain enough air to allow gas exchange in the root system.
Good growing media are also characterized by high hydraulic conductivity, i.e. ability to transmit water.
Another important property is the medium's weight: it should be light weight for easy and less expensive transport and handling. But it should also be heavy enough to provide physical support to the plant.
Growing Medium And Production System Compatibility
It may be surprising, but in order to choose the best medium, the first thing you should do is consider the production system's specifications. These include: the type of irrigation technique (drippers density and discharge), containers size and containers shape. These factors and the growing medium must be compatible in order to obtain uniform distribution of the irrigation water and effective irrigation.
Porosity and Water holding Capacity
Each growing medium has a characteristic particle size distribution. The spaces (pores) between the solid particles can be filled with either air or water and are referred to as "total porosity".
Each medium contains pores of various sizes. Smaller pores can retain water with more force than larger ones. A pore that is too large cannot hold water against gravity, and empties. The higher the pore is positioned in the container, the smaller it has to be in order to retain water against gravity. At the top of the container, pores which are too large to hold water against gravity are empty. Therefore, the top of the container will always be dryer than the bottom. At the bottom of the container, all pores, including the largest, are filled with water, making the bottom layer saturated.
Water Retention Curves
Labs can accurately measure the water percentage by volume (v/v in %) at given heights of the medium, after saturation and drainage. The height is measured in cm and the data can be graphically presented as a "Water Retention Curve". Some labs refer to the height as "tension in cm".
Containers Size and Shape
We mentioned above that the size and shape of the containers, in which the medium is placed, determine the amount of water that the media hold.
If we fill a few containers of the same volume, but different shapes, with the same medium and irrigate to saturation, the water will reach the same height in each of the containers.
The same water content in % will be measured at each height (according to the water retention curve of this medium). But because of the different shapes, the actual amount of water is different in each container.
This results in different water/air ratio in each container and in different irrigation management.
Irrigation frequency and amount of water applied in each irrigation are determined by the available water content of the medium and by the container shape and size. For example, one irrigation cycle a day is not enough, if the water consumption of the plant is higher than the amount of available water in the container medium.
Hydraulic Conductivity
As the name suggests, hydraulic conductivity is the rate in which a medium transmits water. Hydraulic conductivity of media is not routinely measured in lab tests. Nevertheless, it is extremely important to understand its significance. Hydraulic conductivity is in effect the limiting factor of water uptake by plants in container media, rather than the water quantity in the medium.
When transpiration rate exceeds the hydraulic conductivity of the medium the plant cannot efficiently use the water contained in the medium and might wilt. In materials used for container media, the hydraulic conductivity decreases exponentially as the medium dries. This is because continuity of water is disrupted after the larger pores empty.
Guy Sela is an agronomist and water specialist. In 2005 Guy developed a unique software for fertilizer management that help growers to reach higher and better yields, save time and frustration and increase their profits.
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