Introduction:-
Horticultural Perlite has a long and enviable record of performance as propagating and growing medium throughout the world. It has been successfully used in virtually all horticultural applications including glass-house growing, landscaping, lawn, and stadium turf and in a variety of container applications. Times and time again it has proven its superiority in meeting the needs of commercial growers and home gardeners.
What is Perlite?
Perlite is a volcanic material that, when heated to 1600 deg F (850 deg. C°)
Makes an excellent ingredient for plant growing mixes. Perlite particles create
tiny air tunnels, which allow moisture and oxygen to flow freely to roots. This is
important since 98% of all oxygen a plant gets it absorbed through its roots.
Poorly drained growing mixes shut out oxygen; root “ pumps “shut down and
the plant dies from suffocation.
Typical Physical Properties
Color……………………… White
Refractive Index …………… 1.5
Free Moisture, Maximum …….. 0.5%
pH ( of water slurry) …………. 6.5-8.5
Specific Gravity ……………… 2.2-2.4
Grain Size …………………* 0 – 5 mm * 2-5 mm
Bulk Density (loose weight) ………….80 – 100kg/m3
Fusion Point ……… 2300-2450F° ( 1260-1343 C°)
Specific Heat …………... 0.2BtU/lb.F° (837 J/kg.k)
Thermal Conductivity at 75 F°(24 C°) ……………….
27-41 Btu.in/h.ft2 F ( .04-.06W/m.k)
Solubility Soluble in hot concentrated alkali and HF
Moderately Soluble ( > 10%) in 1N N a OH
Slightly soluble ( > 3 %) in mineral acids (1N )
Very slightly Soluble ( > 1% in water or weak acids.
Chemical Composition wt%
Sio2 |
72 - 76 % |
Fe2O3 |
0.5 - 1.5 % |
Al2O3 |
7 - 11 % |
Na2O |
2.9 - 4 % |
K3O |
4 - 5 % |
CaO |
0.5 - 2.5 % |
MgO |
0.1 - 0.5 % |
TiO2 |
0.03 - 0.2 % |
H2O |
2 - 6 % |
Advantages:-
1-Perlite makes moisture, oxygen and nutrients readily available to plants, because of the unique shape of each particle, plus its permanency, moisture and nutrients can cling to the crevices until the plant needs them, while the granular quality provides quick drainage of excess moisture and allows apace
for oxygen– vital for healthy plant growth.
2-Horticultural Perlite particles have a closed cell structure with multiplicity of tiny crevices on their surface. These crevices trap water and hold it against drainage and evaporation, yet making it available to plant roots on – demand.
3-Horticulture Perlite provides more constant moisture status around the roots at all times irrespective of weather or stage of root growth.
4-Perlite ensures more even watering throughout the growing area.
5-There is less likelihood of over-watering with horticulture Perlite.
6-Perlite culture avoid wastage of water and nutrients. floors accurately
7-The use of Perlite eliminates the need to grade growing.
8-It is lightweight it can absorb and provide a large amount of both air and
water, it is sterile and has a neutral PH, and it can be very tolerate of subtle
changes in soil conditions .
9-It is possible to grow most plants in Perlite alone, although usually the finer
grades and medium grades will work better and require less water.
10-Is sterile and free of weeds and disease.
11-Perlite (specially the fine grade) is excellent for drying flowers.
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12- Serves as an insulator to reduce extreme soil temperature fluctuations
