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Fertilizing

There are 10 nutrients/additives to be aware of when fertilizing:

• Nitrogen
• Potassium
• Phosphates
• Magnesium
• Calcium
• Sulphur
• Micronutrients
• Wetting Agents
• Growth Enhancers
• Microbes / Living Culture

 

Macro-nutrients

Nitrogen (N) – This is an essential component of chlorophyll, the pigment in plants that is used to derive energy from the sun to grow. Nitrogen is also the element which is the main building block in protein which allows yours grass to grow. If importance had to be placed on the elements required to get grass growing, Nitrogen would be at the top of the list. A recommended dosage of Nitrogen for your lawn would be between 1 – 2.5kg per 100m² for the growing season. In the South African climate, that would equate to 8 months (September to April). These dosages should be broken down into 4 - 16 equal parts and can be broken down even further to ensure the lawn is constantly fed throughout the growing season. 16 equal parts throughout your growing season is optimal.

 

Phosphate (P) – The element responsible for ensuring roots grow properly. Without a good root system, grass will be susceptible to disease, drought and patching. Over-fertilizing of Phosphate is harmful to the environment, especially when it starts to leach into the water system. Keep Phosphate fertilizing at the lowest level possible.

 

Potassium (K) – Sometimes overlooked, this is an absolute must have. Potassium is responsible for regulating photosynthesis, without which any plant simply will not grow. It regulates the osmolarity in plants and their ability to hold onto water. It plays an important role in activating various growth enzymes in grass and activates it’s production of both starch and protein. Potassium is as important as Nitrogen in ensuring your grass is healthy all year round.

 

“Micro” Macro-nutrients

Sulphur (S) – This is the lawns “immune booster”. It is not required to focus on fertilizing with Sulphur as it is often found bound to Nitrogen in your fertilizer as Ammonium Sulphate, but it is important for the lawn’s food production.

 

Calcium (C) – Very important in the structure of the grass leaf and root system. A shortage of Calcium will display as grass looking ‘floppy’ and not standing up properly. Most chemical fertilizers will contain calcium as a filler in the form of Limestone, without you knowing.

 

Micro-nutrients

Iron (Fe) – The main element in Chlorophyll, similar to humans’ the red colour in your blood is from haemoglobin, the green colour in lawn is Chlorophyll. Supplementing Iron on your lawn gives it a deeper green (when done correctly), too much can cause browning. Iron also assists in the prevention/treatment of moss, algae and mould. If the 3 main Macro’s are applied correctly (N, P and K), Iron is the final nutrient ensuring a deep green lush lawn. APPLY IRON ON YOUR GRASS ONLY, IT WILL STAIN WALLS, DRIVEWAYS, STONE PATHS AND EVERYTHING ELSE WHICH IS NOT PLANT BASED.

 

Magnesium (Mg) – A carrier of Phosphates in your grass and involved in photosynthesis.

 

Manganese (Mn) – A shortage of Manganese can reduce pigmentation(Chlorophyll production) and cause browning. Generally acidic (pH under 7) soils will have sufficient Manganese to support healthy grass. Sandy soils with a pH higher than 7 (alkaline) are potentially susceptible to Manganese shortage.

 

Copper (Cu) – This micronutrient is also involved in Chlorophyll production. It is an activator/regulator for certain enzymes in the lawn.

 

Amino Acids – The building blocks of protein, supplementing at the correct dosage of amino acids is a precise science. Some Amino Acids, like Glutamine, can be used to stimulate and stunt growth. There is an advantage to using amino acids to feed the lawn Nitrogen – many studies on hydroponic growing of various plants and vegetables have shown that better results can be achieved supplementing amino acids in place of Urea or Ammonia. Amino Acids worth mentioning are L-Glutamine, L-Glycine and L-Methionine.

 

Other Additives

Wetting Agents – These may be marketed as soil aeration or water saving products. The scientific term for a wetting agent is a surfactant, i.e. when added to water it reduces the surface tension of water. This allows the water to penetrate deeper into the soil and carry nutrients to ‘force’ grass to grow deeper roots with less watering and using a wetting agent. Deeper roots = healthier more drought resistant grass.

 

Humic and Fulvic Acid – Generally found together in fertilizing products with the humic acid concentration being the highest. These are not overnight treatments which will improve your lawns appearance like Iron. They are long acting soil enhancers which, over regular use and prolonged periods of time, can create an optimal environment for lawn to grow (if the soil has been fertilized properly with macro-nutrients). Benefits include: better seed germination, stabilization of soil pH, higher uptake of nutrients from soil, aids in water and nutrient retention in soil, improves microbial activity in soil, assists in better root growth, aids in enhanced plant growth and generally improve total soil condition. Liquid application of Humic Acid can be difficult with a fine nozzle as many products on the market may not be fine enough to pass through the nozzle effectively.

 

Kelp / Seaweed – More specifically Cool Atlantic Kelp, has been recognized as a great fertilizer for lawns. It contains a range of nutrients for your soil, as well as very important Auxins and Cytokines (hormones which help root and foliage growth). Some kelp species have been known to grow up to 60cm in a day. Cool Atlantic Kelp has an ideal ratio of Auxins and Cytokines to give your lawn a the boost it needs. Benefits of using Kelp regularly include:

• Increased root mass / growth
• Deeper green colouration of leaves
• Assist in soil holding onto watering
• Increased growth of foliage
• Improved Nitrogen availability in the root zone
• Increased microbial activity
• Increased uptake of nutrients in plants from soil
• Improved drought and disease tolerance

Always remember to let your kelp sit on your lawn for at least 3 – 6 hours prior to watering

 

Understanding the label of your fertilizer

5:1:5 (20): the first 5 refers to the Nitrogen (N), the 1 refers to Phosphate (P) and the 2nd 5 refers to Potassium (K). The (20) means that only 20% of the contents are active ingredients and the rest are fillers. To further explain this:

 

(5 N + 1 P + 5 K) = 11 parts in ratio

10kg * 20% = 2kg of active ingredients

2kg / 11 (parts in ratio) = 0.182kg roughly

Therefore there you get:

Nitrogen 0.182kg x 5 = 0.91kg roughly

Phosphate 0.182kg x 1 = 0.182kg

Potassium 0.182kg x 5 = 0.91kg roughly

Total Actives 0.91kg + 0.182kg + 0.91kg = 2.00kg

 

If you use a fertilizer with a ratio of 5:1:5 (20), optimal for grass, you know that 1 bag (10kg) every 2 months is the MAXIMUM you can use, remember more isn't always better. Faster growing grass means mowing more often to remain within the ⅓ rule. Rather break up your fertilizing into a smaller, more frequent application. In the beginning of the growing season aim for ¾ the maximum dosage over 1 month. With the above fertilizer this would be a quarter of a bag, then follow this up every 2 – 3 weeks going forward.

When entering autumn (in the South African Climate), look at something that has a lower Nitrogen content with a higher Phosphate and Potassium content like a 2:3:2, this will push root growth before the winter time and give your grass the best chance of bouncing back in spring after potential winter dormancy.

 

Taken all the above into consideration, a combination of the two types of fertilizers is probably the best solution. Early in the growing season, a good chemical fertilizer dosage can kick start the grass for the rest of the season. Organic fertilizers can be staggered with the chemical fertilizer, however, a liquid organic fertilizer is the best bet. If you are cutting your grass as often as should be and ‘bagging’ clippings, the organic granular fertilizer will never have enough time to take effect.