Basic needs of plants By Allah Dad Khan

2. Basic Needs Of Plants
By Allah Dad Khan
Agriculture Adviser To
Sohny Dharti TV
Pakistan

10. During photosynthesis, plants take
carbon dioxide from the air and use it
to produce food for their growth. What
is left over after photosynthesis is
oxygen, which they put back into the
air for us to breathe. Dirty air blocks
sunlight, which is also necessary for
plants to grow, and may prevent plants
from absorbing enough carbon dioxide.

11.  Sunlight
 Sunlight is used by plants to convert carbon
dioxide and water into sugars through
photosynthesis. In the absence of sunlight,
plants cannot produce the food that they need
to thrive. Plants that do not get enough sunlight
will have thin, spindly stems that lean toward
the light and may wither and die if more light is
not received. Plants that receive too much
sunlight will grow poorly, as well, becoming
bleached or blistered. A plant that requires full
sun needs eight to 12 hours of unfiltered sunlight
per day, and one that requires partial sun needs
from five to six hours. Plants requiring partial
shade need indirect or filtered light, and should
only receive direct sunlight for short periods of
time each day.


13. Water
Like all living things, plants need water to
survive. Water is the conduit for nutrients
and food that plants need. The amount of
water needed will vary for different types of
plants, because some, such as African
violets, prefer moist conditions and others,
such as cactus and succulents, prefer drier
conditions. As a general rule, if the soil
feels dry to the touch, plants should be
watered.

20. s
There are three main nutrients that plants get from
soil: nitrogen, phosphorous and potassium. In
addition, there are secondary nutrients and
micronutrients that are also obtained from the soil
plants grow in. The amount of each nutrient
required varies with different types of plants, and
too much or too little of certain nutrients can stunt
growth, produce weak plants or even cause them to
die. As plants use the nutrients in the soil, they must
be replenished with soil additions or fertilizers, or
the nutrient content will eventually be diminished.

21. The amount of space available has a
direct bearing on plant growth. Plants
with a large area to grow in will extend
their roots and thrive. Plants that are
crowded or have only a small space in
which to grow will have tight, crowded
roots, resulting in stunted growth.

22. In cold climates, few plants can survive, so
there is little greenery to be found. Some
plants, such as geraniums, require
temperatures to be at least 80 degrees F in
order to thrive and grow. Other plants can
withstand colder temperatures, but very
few can survive temperatures that are
below freezing. Temperatures should
usually be close to that of a plant's native

37. We humans--and all animals for that matter--must eat
food
to supply our bodies with energy. Plants, on the other
hand, have the remarkable ability to manufacture their
own
food! Plants "harvest" the energy of the sun then use
this energy to manufacture sugars.
This process is called photosynthesis. In addition to
sunlight,
plants need water and air to perform photosynthesis.
They
use mineral nutrients, the fourth basic need, to build
the
necessary cell structures.

40.  Plants also need water for things besides
photosynthesis. They need water to maintain cell
pressure--pressure within the plant's cells is what keeps
stems sturdy and leaves opened to the sunlight. But
plants lose lots of water during a process called
transpiration, during which water vapor escapes from
pores on the undersides of the leaves. Why should
gardeners care about transpiration?
 Because one of the most important factors in growing
healthy plants is maintaining proper moisture levels.
The rate at which a plant is transpiring has a huge
effect on how much water it needs!
 The warmer, drier, windier, and sunnier it is, the more
water a plant loses to transpiration. During dry weather,
you
 need to replace this lost water, or plants will wilt.

41. Vegetable plants need plenty of water throughout the entire
growing
season. Apply 1 to 1 ½ inches per week in a single watering, unless
rain does it for you. Light sprinklings may do more harm than good
because roots tend to form near the surface of the ground if water
doesn’t penetrate deeper. Shallowly rooted plants are more
Susceptible to drought damage. Sandy soil requires more frequent
watering than heavy clay. However, always apply water
slowly so it can soak in. Check the amount applied by catching it in
straight-sided tin cans placed throughout the garden, or by digging
down to see if the moisture has penetrated at least 6 inches.
Inexpensive plastic rain gauges are also available

42.  You've probably heard that the ideal garden soil is a rich
loam.
But what exactly is this?
A rich, loamy soil contains a range of mineral particle sizes—
—
from microscopic clays to relatively large grains of sand.
These particles are bound together into groupings of various
sizes called aggregates. Soil composed of these aggregates
has lots of
pore spaces of various sizes, and these spaces contain water
and air. If
all the spaces contain water, the soil is waterlogged; few
plants can
withstand such saturated soils for long, because plant roots
need air.

43.  A soil test is the only way to know what nutrients
your plants need. Your soil test results tell you how
much
and what type of fertilizer your plants need, tells you
the
soil pH--how acidic or alkaline your soil is .
 Also tells about micronutrients and lead. Soil test
Results depend on how well you take the soil sample.
 The sample should reflect the overall lawn or garden
condition. Make a representative sample by collecting
Small amounts of soil from various spots within the
target
area.

44. Choose the spot in your yard that has the best
soil. You may be able to distinguish the quality
of your soil by looking at your lawn. If it looks
lush and healthy, then the soil supporting it is
probably good for a garden. Don't pick the spot
where the lawn is the worst, and figure you
can get
out of reseeding by locating your garden there.
And
avoid low spots that stay wet in the spring.