PLANT GROWTH & PHYSIOLOGY. (Part 5)
There are three classes of plants. Each of these classes metabolize in a different way. The first class are succulent plants called CAM. These plants like low light and high humidity levels and so thrive indoors, in bathrooms and kitchen areas.
The second class of plants is called C4. These plants grow in hot arid regions and are very efficient at using both Carbon Dioxide (CO2) and Sunlight. Most C4 plants are grasses.
The third and last class of plants are called C3. These plants join two 3-Carbon atoms together to produce sugar. The chemical formula for sugar is C6H12O6 which is 6 Carbon, 12 Hydrogen and 6 Oxygen atoms stuck together. Most of our favourite plants are to be found in this class.
HOW DOES A PLANT WORK?
Like all living things, plants breathe 24 hours a day. In order to make energy each plant cell respires (converts plant sugar to energy). The plant uses Oxygen (O2) and expires, or breathes out, Carbon Dioxide (CO2).
In the same way that energy moves around the human body, so water, nutrients and plant sugars are continually being transported around the plant body. The leaves create a circular flow with the roots. This circulation occurs when the leaves draw up, water from the roots, through their Xylem.
These are straw like cells found in the plant stem. The water continually evaporating from the leaves sucks up more water from the roots and creates the internal water pressure that keeps the plant rigid. Thus if the plant is deprived of water, as in a drought, it loses its rigidity and begins to wilt when the internal pressure drops.
The leaves return energy to the roots in the form of sugar solutions. These are transported from the leaves via the plants Phloem. These are also straw like cells found in the plant stem. In this way the leaves exchange sugars for water and nutrients, while the roots exchange water and nutrients for sugar solutions. This liquid circulation is constant and continuous throughout the life of the plant.
THE MAIN PLANT PARTS.
The 3 main parts of a plant are the Roots, the Stems and the Leaves. Each of these parts is of great importance and any problem that arises in any of them will be a major one. The most sensitive part is the roots, as well as being the most difficult to see should a problem occur.
The Roots:
The miracle of growth starts at the roots. As already mentioned, roots transport nutrients up to their leaves and plant sugars are returned by the leaves. The roots also act as storerooms for the excess sugars that are produced by the leaves. These sugars are stored in the form of starch. The size of the root ball and therefore the amount of starch that can be stored, determines the success of the plant in terms of growth and productivity.
The size of the root system is directly affected by the amount of moisture, the temperature, the available Oxygen and the supply of plant sugars being transported down from the leaves. According to Graham Reinders, in his book "How to Supercharge Your Garden", a research Rye plant in a 12 inch pot was said to have had 14 billion root hairs. These hairs would have stretched 6200 miles (nearly 10,000 km) if placed end to end and covered an area of 180ft by 180ft (about 55m by 55m). The greater the root system is the more energy (starch) it will be able to store and so, the more nutrients it will be able to send up to nourish the leaves. The plant will then have the capability to grow stronger. The end result of this is that the leaves will be able to pass more plant sugars back down to the roots and so the cycle continues.
Another factor to be taken into account is the root medium. Plants take their nourishment from the medium surrounding their roots. It stands to reason that the less energy the plant has to expend in order to get that nourishment the more energy it will have available to use for growth and nutrient exchange with its leaves. Because a plant takes most of its water in via its roots, (the root hairs trapping the water molecules surrounding it) and transpires about 99% of that water out via its leaves, it will wilt and fall over if its roots cannot extract enough water out of its surrounding medium.
A plant growing in the ground will take its moisture from the surrounding soil. This moisture normally gets into the soil as rain and the plant absorbs that rain and the nutrients that have dissolved in it, via its root hairs. After the rain has stopped the topsoil quickly dries out as the water filters into the ground. Because of this drying out the plant has developed a means of absorbing Oxygen via its upper roots. The top third of the roots become specialized as "Air Roots" while the bottom third becomes specialized as "Water Roots".
It is vital to ensure that the Air Roots are not kept constantly wet as this will result in the plant drowning. The Water Roots however, may be kept wet all the time, providing that the water has sufficient Oxygen dissolved in it. Insufficient Oxygen will result in roots with brown, discoloured root tips and subsequent infections. Healthy roots are a crisp, white looking structure.
The plant is quite capable of healthy living with the roots exposed to light as long as they remain moist. However, light will encourage the growth of Algae which will cause odours. The Algae will also compete with the plant for Oxygen during the dark periods and nutrients in the light ones. This, of course will mean the plant has to work harder in order to produce sufficient sugars for its needs. The Oxygen produced during the dark periods is used to help the roots convert these sugars, from the leaves, into energy (Starch).
Copyright (C) 2004, 2005.
J R Haughton. ITEC MIPTI
--- All Rights Reserved ---
A partner in a thriving retail Hydroponics supply business, Rickie Haughton is the owner of hydroponics-gardening-information.com which aims to cater for all levels of expertise in the field of hydroponics gardening. The website is packed with good content about all aspects of Hydroponics Gardening, offers a free Club Membership to all subscribers and access to our Blog.
![]() |
|
![]() |
|
![]() |
|
![]() |
Indoors or out, you'll find miniature roses very easy to... Read More
Most businesses consist of the owner only or the owner... Read More
Part Two in a SeriesOnce you have your landscape design... Read More
Fruit gardening and vegetable gardening is a very exciting venture.... Read More
As the curtain of winter lifts, tulips are one of... Read More
So, you have decided to plant rose bushes in your... Read More
What could be more relaxing than gardening on a nice... Read More
So. The water garden bug has bitten. You've dug and... Read More
One winter evening I was working on the computer when... Read More
Traditionally Hindu tepmples were located either on hills or forests... Read More
Why Compost?Recent studies show that an average family throws away... Read More
Do you love to sit outdoors and swing for hours... Read More
IntroductionSo you've decided to build your very own backyard water... Read More
No, ghosts of the Donner Party have not started haunting... Read More
If your fish hang out at the bottom of the... Read More
Women take pride in home decoration and gardening and want... Read More
Hi there,I am Jhon Saunders and recently took up gardening... Read More
Rising from a muddy pond, a lotus flower blossoms. Such... Read More
This is a project I've had on the back burner... Read More
These days, it's easy to get lost in the wealth... Read More
During my youth kids were required to pass through a... Read More
You might be tempted to let Mother Nature, tend to... Read More
Think "outside of the box" when sending your next floral... Read More
Most of us regard a sundial as an attractive ornament... Read More
Decorative Birdhouses are active garden ornamentation --the presence and movement... Read More
Visualize watching a bright green hummingbird in your garden moving... Read More
Surprisingly enough, it is usually in mid-summer that many gardeners... Read More
Having an ultra violet pond filter will give you a... Read More
A focal point is an important design element; it is... Read More
THE BASICS OF HYDROPONICS.What Do Your Plants Need?All plants need... Read More
Though most Push Reel Mowers made today are durable, they... Read More
When planning your new landscape, the first place to start... Read More
Dried plants and dried flowers are midway for people who... Read More
I recently bought a small tractor for my garden, which... Read More
Perhaps you were browsing the pages of a catalog and... Read More
To care for your antique ceramics you need a gentle... Read More
Summer is here and it's time to plant and enjoy... Read More
Compost, made from decomposed grass clippings, leaves, twigs, and branches,... Read More
Severe environmental stressors are the most frequent causes of sudden... Read More
Snow peas may have been named because in bright sunlight... Read More
If you have never grown vegetables before the first thing... Read More
Many finer homes and businesses feature beautiful indoor and outdoor... Read More
There is no mention to be found of female leprechauns... Read More
Today's successful water garden usually is designed as an ecosystem... Read More
Some might ask, "Why grow Italian vegetable seeds?" Why bother... Read More
A property that has a well manicured lawn has one... Read More
Yes! You can attract hummingbirds to your home. Even if... Read More
You can have different water pond designs, however ones that... Read More
Parthenocissus tricuspidata is commonly known as Boston Ivy, Cottage Ivy,... Read More
Deciduous trees dazzle us with the brilliance of the golds,... Read More
Container gardeners take note. Tired of clay pots? Think vintage,... Read More
Everyone seems to love a secret -- and when the... Read More
This may seem contradictory, but you want to leave a... Read More
DendrobiumsThis month I am focusing our attention to the care... Read More
The Mentha species or mints as they are commonly called... Read More
To achieve Koi pond aeration, there are some things you... Read More
Preparing for the Winter Months: Gardening in OctoberWhen you feel... Read More
Twentieth century American architect Phillip Johnson once said, "I hate... Read More
Every Garden can benefit from the addition of container gardens.... Read More
Summer is over, but for many of us - the... Read More
Early in May here in west central Wisconsin, I can... Read More
Do cat repellents work? How to stop a cat from... Read More
We have once again reached the wonderful magical time of... Read More
It's August, the weather has cooled a bit here and... Read More
There are several different ways to manage algae in your... Read More
Proper pruning of your backyard grapevines is essential to maintain... Read More
Landscaping & Gardening |