Having been involved in pasture development and pasture seed production for 25 years, we can offer advice on pasture types for coastal soils, and planting and maintaining the pasture for continuing grass production.
I must stress the point that you only get back what you put in. In other words, if you don’t prepare and treat the soil adequately with fertiliser then you will end up with a non-productive pasture which will become over-run with weed infestations.
These photos below show how pastures can be grown in this country. They are photos of our previous property. You can grow pastures like these with correct management techniques.
Soil preparation is essential for establishing a productive pasture. An ideal preparation is ploughing and then offset disking the ground, and then levelling as above.
Pastures are expensive to establish and maintain, but if done properly, you can have pastures like those shown in the above photos.
There are no shortcuts to soil fertility, and because fertiliser prices have varied greatly in the past couple of years, you cannot reduce fertiliser rates because of costs.
Also, people have asked about liming. It is cheaper but liming only changes the soil pH and has nothing to do with phosphate, nitrogen and potassium levels (although it may assist in the uptake of nutrients to the plants).
We found that pH levels in our area are around 5 to 6.5, and with these readings lime was not necessary as improved pasture plants grow well in this range. If your pH was below 5, liming would be beneficial.
This element is deficient for sown pasture development in Hervey Bay coastal soils. It is supplied by legumes or by applying a nitrogenous fertiliser such as urea (46% N) or nitram (34% N). Urea should only be applied when there is a reasonable chance of rain within a few days of application.
The majority of produces rely on legumes to supply the nitrogen requirements for the grass component of the pasture. Legumes are herbaceous plants which form a symbiotic relationship with the nitrogen-fixing bacteria Rhizobium. These bacteria are able to convert atmospheric nitrogen into a form available to plants.
Legumes have specific nutrient requirements (particularly phosphorus) and some will need to be inoculated with the correct strain of Rhizobium at sowing. Many legumes also have specific management requirements such as strategic spacing and maintenance fertiliser.
If adequate phosphorus is not available, nitrogen fixation can be affected and, subsequently, the growth and feed value of the legumes in pastures. Phosphorus is deficient in most coastal soils. It is usually applied as superphosphate (9% P: 11% S), but can also be applied as DAP (diammonium phosphate 18% N: 20%P). One bag of DAP provides as much phosphorus as two bags of super, and as much nitrogen as half a bag of urea.
DAP can be used for establishing pastures. The nitrogen content improves pasture establishment on infertile soils, and helps the establishing pasture to compete with woody and herbaceous weeds.
This element can be deficient in some soils. It is usually applied as superphosphate (11% S).
This element is deficient in the coastal lowland (Wallum) soils and can become deficient in other soils under intensive production systems such as irrigated ryegrass and hay production. It is usually applied as muriate of potash (50% K).
Deficiencies of copper, zinc and molybdenum occur in the coastal lowland soils and must be corrected when the pasture is first established. Two methods can be used to correct these deficiencies. The most common is to apply Cu Zn Mo superphosphate to which these trace elements have been added. The alternative application method is to mix the trace elements in water and spray on with a boom spray.
Some pasture legumes such as siratro and Wynn cassia have a high requirement for molybdenum in order to fix nitrogen and grow well, while others such as the stylos and Lotononis have a lower requirement and do not usually require extra molybdenum.
Maintenance fertiliser is required to maintain soil fertility and animal productivity.
Superphosphate and muriate of potash are top-dressed annually on coastal lowland soils in winter or spring. Application rates range from 125 to 200 Kg/ha (50 to 80 Kg/acre) superphosphate and 50Kg/ha (20Kg/acre) muriate of potash.
On our pastures, we alternate between the above maintenance application and 125 Kg/ha (50Kg/acre) of DAP every second year.
Rhodes grasses are suitable for coastal areas as they will tolerate lower fertility soils. This is especially true of Katambora and also Callide, which requires a higher rainfall area than Katambora. Rhodes grasses will also slightly tolerate low salt areas.
A new paspalum variety called Blue Dawn is showing promise as a species for areas throughout Queensland. Bluegrass will grow in different areas on better drained soils, and we have put it in our coastal mix.
Pangola is a good pasture (Digitari) species, but unfortunately will only grow by runners as pangola seed is sterile. Strictland is a relatively new Digitari species which we were growing and producing seed from, and is similar to Bluegrass in that it will grow on the better coastal soils.
Lotononis was by far the best legume suited to coastal areas. We used to produce it, but it is no longer available. Therefore, we have added a mega combination of 3 Stylos species and the relatively new Burgundy Bean to our mix. Wynn cassia will grow in the area, but do not plant it if the pasture is to be utilised by horses.