Time to fertilise your lawn!
You may remember your Grandad mixing his own fertiliser consisting of Sulphate of Ammonia, Dried Blood and Fish and Bone Meal - sounds ghastly and it probably was. It is still possible to purchase straight Sulphate of Ammonia as a lawn fertiliser and good old fashioned Growmore. These age old Nitrogen sources are likely to scorch your lawn, especially Sulphate of Ammonia as it has a Nitrogen content of 21% straight Nitrogen - a generating real flush of growth and then the benefit quickly reduces and is gone.
One important problem of not keeping your lawn topped up with available nutrients is that the lawn disease, Red Thread will quickly appear. You have been warned and there is plenty of it around currently.
Nitrogen expressed as a N on the label analysis, N 22 in our case. It is the nutrient that is responsible for vegetative growth and mostly colour. It is used by the plant in the formation of chlorophyll molecules, which are involved in photosynthesis. Nitrogen is a very mobile element. When it is deficient, the proteins of older leaves are converted and then transported to the younger ones. The older leaves then become greener and then yellow, before the necrosis (dying) of the leaf blade.
Phosphorus expressed as a P on the label anyalysis, P 5 in our case. It has been described as the workhorse of a plants nutritional process. Phosphorus is an essential macronutrient contained in every living cell withing the turf grass plants. It is involved in a number of physiological functions within the plant, including: Energy transformation as a constituent of the genetic material of the cell nucleus. It is responsible for Carbohydrate transformations such as the conversion of starches to sugars and also Establishment, Rooting Maturation and Reproduction of the plant. It occurs in large amounts in young tissues, especially in the regions of cell division. As a plant matures, the Phosphorus is transferred to the reproductive areas and eventually accumulates in the seed. It is vital during the seedling stage of turf grass growth and development; therefore, phosphates should be placed near the seeds during planting to aid rapid establishment. It also stimulates root growth and branching (tillering) and seed setting is enhanced. High phosphorus levels hasten maturity; low levels delay maturity. Phosphorus is insoluble and is often found in the upper layers of the soil, where it can be absorbed by the roots. Phosphorus absorption is greatest at a soil pH of 6-7 and during periods of active growth.
Potassium expressed as a K on the label analysis, K 10 in our case. It is not a fixed constituent of living cells, but is essential in growth and development processes. Potassium functions in: Carbohydrate synthesis and translocation, supporting the chlorophyll tissue – aids photosynthesis in low light intensities. It is responsible for catalyzing numerous enzymatic reactions, including nitrogen reduction, regulating transpiration, controlling the up-take rate of certain nutrients and regulation of the respiration rate. Potassium favours the development (thickness) of cell walls, thus making the plant more resistant to heat, cold and frost conditions. It increases the plants ‘wear tolerance’, speeding up the recovery period by speeding up the translocation of necessary materials to meristematic tissues and encourages rooting. High levels of potassium tend to reduce the incidence of the fungal diseases, like Dollar Spot, Fusarium Patch, Dry Patch and Red Thread. Potassium’s role in the plant is that of regulating the plant’s processes. Potassium is known to influence at least 46 different enzymes within the plant. Turf grasses require Potassium in relatively high amounts – second only to Nitrogen. The Potassium content is quite high in young, actively growing turf grass plants, but content decreases rapidly as they reach maturity. It is absorbed and stored in plant tissues in much larger quantities than is required for normal growth and development, when larger amounts are available in the soil. This excessive consumption is called ‘luxury consumption’. Potassium is prone to leaching from the leaf tissues and the Potassium content of soils varies greatly, but is usually greater than Phosphorus or Nitrogen. Although the total content may be high, only a small amount is available for uptake by turf grasses. The use of nitrogen fertilizers containing Sulphate of Ammonia, also increase Potassium loss by leaching.
In a typical lawn fertiliser you will see an analysis written like this - 22-5-10. This is represented as N 22, P 5 and K 10. In the early spring months an analysis such as this is perfect. As we head towards autumn, you are aiming for less Nitrogen but more Potassium.
The more modern granular and liquid Methylene Urea Nitrogen, new Stabilised Nitrogen and Sulphur Coated Lawn Fertilisers favoured by many a lawn treatment company have a mechanism of controlling the release of nutrients available to the turf grasses over a period of two to three months by a bit of technologically clever engineering. There is no immediate rush of growth but a steady release so you will not get up a sweat trying to keep up with the lawn mowing.
Should you have a large area of grass to fertiliser with either a granular or liquid formulation, please email us.