What is sub surface irrigation?
Subsurface irrigation or sub irrigation allows the precise application of water, nutrients and other agro- chemicals directly to the root zone of plants.
Irrigating underground is one of the most efficient ways to water plants. Subsurface irrigation reduces evaporation, wind drift, over spray, vandalism and as such can save substantial amounts of water.
The depth and placement of the drip-line depends on the soil and need of the plant being irrigated. Water moves by capillary action through the soil, 150-750mm beneath the soil surface, forming a continuous wetted layer at the root zone.
Porous membrane hose
Porous membrane hoses are installed underground at a suitable depth and distance apart from each other depending on the soil conditions.
Due to a special quality of the type of hoses used in the system process, the pores react sensitively to gentle positive or negative pressure.
Each function can run automatically depending on results received by measuring equipment.
Different application for porous membrane hoses
- Positive pressure H²O or Air [supply of oxygen]
- Negative pressure H²O or Air [aspirate of oxygen]
Possible water reduction from 25l/m²/d down to 5l/m²/d
Sub Surface Water Storage using Polymer products
Water storing polymer products are manufactured in several product types, mostly for the commercial industry as an effective water management aid.
Special water storing polymers have been developed to assist commercial growers, nurseyman and interior/exterior landscapers in growing and maintaining vigorous plants.
Typical applications are in the landscape industry for bare root/seedlings or transplanting, for broad area treatment like flower beds or ornamental gardens, for turf/sodding or for golf courses and greens or for greenhouses and nourseries.
Different sizes of polymers for different purposes
This synthetic polyacrylat polymer has a particle size between 0.2mm and 0.85mm with a potassium salt base. It will absorb up to 200 times its weight in tap water. Its application is mainly for amending turfs and potting soil but also applicable for forestry, landscape or nursery trade.
With a particle size of 0.5mm to 3mm this is a synthetic polyacrylamid polymer with a sodium salt base. This polymer will also absorb 200 times its weight in tap water and mainly used for planting green goods, transplanting trees, shrubs etc.
Depending upon the pH of the soil, soil type and percentage of salt in the soil and water it will work effectively in the soil for several seasons (4-6years).
Both types of polymers have been modified to control the rate at which water is made available to the plants. When mixed in the soil the chrystals will soften and swell as water is added and absorbed. When the soil dries, the polymer will slowly release its water to the plant.
It acts as a water reservoir, even during periods of drought the stroed water is released to the plant. The expansion and retraction of the polymer during the watering cycle helps soil aeration which is important for all plants.
Benefits of subsurface water storage
- Reduces plant watering by 50%
- Reduces plant watering in combination with subsurface irrgation up to 80% (3l/m²/d)
- Helps reduce soil compaction
- Will not float to the surface
- Increases soil aeration due to expansion and retraction
- Lasts for several seasons
- Increases water holding capacity especially in sandy soil
- Reduces soil erosion
- Reduces surface water run off
- Improves survival rate of seedlings
- Increases yield of agricultural products
- Scientifically proven test results
Download factsheet "Water Storing Polymer" (A4, 2 pages, pdf)
Download factsheet " Porous Membrane Pipes" (A4, 2pages, pdf)
Application and dosing of Polymer
Application for garden and external greens
Take 30gr per running meter of digged earth or
80g per m² flower or vegetable area or
50g per 25 liters of earth.
Work the polymer into the ground and distribute it around the root zone.
If you want to reimplant or new seeding use the recommendation in the table "potplants" further below.
Application for grass surfaces
For grass seeding use 80-100g polymer for 1m² grass surface. Work the polymer 15cm into the ground and irrigate it with plenty of water.
Application for trees, bushes etc
Per 30 cm diameter of root zone use 50g of the polymer. Use half of that quantity in the open plant space. Insert the plant and mix the other half with the rest of the earth to fix the plant. Cover the rest of the whole with 3-5cm untreated earth and irrigate with plenty of water initially.
Application for new pot plants and balcony plants
Mix the appropriate amount of polymer with the equivalent amount of earth. In addition distribute the polymer evenly in the root zone. Fill the pot with the root/polymer mix and cover the top 3-5cm with untreated earth. Then water it properly. Only fill the whole plant pot with a maximum of 80% of earth/polymer mix so that the polymer can enlarge properly.
Pot diameter
15 cm with 3/4 tea spoon ca 3g
20 cm with 1 tea spoon ca 4g
25 cm with 2 tea spoons ca 8g
per m with 7-8 tea spoons ca 30g
Application for existing pot plants
Drill different holes very carefuly into the ground with a long and narrow tool. The holes should be as close as possible to the roots without actually damaging them. Fill the holes with the polymer according to the above table , close them with untreated earth and water it properly.
