The most important variable affecting plant growth is light exposure, and it is therefore important to measure the amount of light your plants receive. Prof Gert Venter explains how this is done.
The most important concept to understand when growing plants is the rule of limiting factors, which determines plant quality. Hydroponics cannot compensate for poor growing conditions, such as improper temperature, insufficient irrigation, nutrient deficiencies, pest and disease problems, or poor light.
Light is the most important variable influencing plant growth.
If plants do not receive enough light, they will not grow at their maximum rate or reach their maximum potential, regardless of how much of any other variable – water, growth medium or fertiliser – they receive.
INCREASING LIGHT INCREASES YIELD
Light is the driving force for photosynthesis, a plant process that changes sunlight into chemical energy. During photosynthesis, water is split in a chemical reaction in which it is separated into oxygen and hydrogen, and carbon dioxide (CO 2) is converted into sugar. A general rule of thumb is that 1% more light will give you a similar percentage increase in plant growth, resulting in a 1% higher yield.
All plants require light and CO 2 for photosynthesis. Adequate spacing between plants will ensure that each plant receives sufficient light in the greenhouse. Tomato plants pruned to a single stem are spaced at 2,7 plants/ m 2 to three plants/m 2 . Seedless cucumbers, with their larger leaves, require almost double this spacing. Hydroponic lettuce spacing varies from 2,5cm 2 for first-stage seedlings to 15cm 2 for final spacing.
This story is from the {{IssueName}} edition of {{MagazineName}}.
Start your 7-day Magzter GOLD free trial to access thousands of curated premium stories, and 9,000+ magazines and newspapers.
Already a subscriber ? Sign In
This story is from the {{IssueName}} edition of {{MagazineName}}.
Start your 7-day Magzter GOLD free trial to access thousands of curated premium stories, and 9,000+ magazines and newspapers.
Already a subscriber? Sign In
Review: the Toyota Hilux 2.8GD-6 DC 4×4 GR-Sport III
The third iteration of the Hilux GR-Sport has finally achieved a sense of presence and style befitting its raceinspired branding. But is this the ultimate modern Hilux? Car Magazine takes a closer look.
Why maize prices soar in Kenya and Malawi but not Tanzania
Namhla Landani, an economist at the Centre for Competition, Regulation and Economic Development, University of Johannesburg, and Arthur Khomotso Mahuma, economist and researcher at the Centre for Competition, Regulation and Economic Development, University of Johannesburg, analyse the issue.
Wet carcass syndrome: a scourge in SA sheep farming
Wet carcass syndrome continues to take a huge financial toll on South African sheep farmers. Octavia Avesca Spandiel spoke to two experts about the ongoing genetic research aimed at addressing this issue.
Pollination innovation
Bee-Tech Group is transforming South African agriculture with pollination technologies that boost crop yields and enhance sustainability. Founder Michiel Bruggeman spoke to Octavia Avesca Spandiel.
The valuable addition that makes this farm tick
Owning the value chain provides farmers with far more control over their produce. However, it requires a fine balance between production and ensuring there is a strong and steady market. Lindi Botha visited Rosemary Hill to find out how this essential oil producer leverages hospitality to make the farm viable.
The benefits of recirculating aquaculture systems
A powerful set of attributes has established recirculating aquaculture systems as a cornerstone of global temperate fish farming, writes Leslie Ter Morshuizen, owner of Aquaculture Solutions.
Minister has big plans for emerging and commercial farmers
DA leader and Minister of Agriculture John Steenhuisen spoke to Glenneis Kriel about his priorities for his department over the next five years, including an increased focus on biosecurity.
New study aims to make wheat more disease resistant
A recent international study explains how bread wheat has helped to transform the ancient world on its path to becoming the iconic crop that today helps sustain a global population of eight billion.
Conservation farming and biodiversity boost soil health and sustainability
A recent academic event focused on research into the links between soil biodiversity, soil health and sustainable agriculture
What has led to the unparalleled rice shortage in Japan?
Japan is facing a rice shortage amid concerns about a potential 'megaquake', several typhoons and an annual week-long holiday, which has led to an increase in panic buying.