For successful establishment and persistence of lucerne, soil conditions need to be considered:
A soil test is recommended before sowing lucerne as it will not tolerate acid soils with high aluminium. Soil pH should be around 5.5-6.5. If the soil is acidic lime is recommended to raise the pH level.
Lucerne requires free draining soil types and does not like waterlogged conditions. To get the most out of your lucerne stand choose a paddock that can be rotationally grazed.
For higher rainfall southern regions, successful spring sowing of lucerne is achievable. This is due to control of winter weeds and rising soil and air temperature aiding establishment. Autumn sowing is recommended in low-medium rainfall regions where the majority of annual rainfall occurs in winter.
Preparation for sowing lucerne is the key. Weed removal through spraying of glyphosate is recommended to achieve a knockdown. For autumn sowing lucerne, spray topping in the previous spring to reduce seed set of annual weeds before the autumn is another option. If the soil test suggests the pH needs to be raised, incorporation of lime can occur; this starts the process to turn the paddock into a fine, firm, weed free seed bed. Pre-emergent herbicide such as Trifluralin can be used at sowing to control weeds to give the lucerne the best chance to establish. Lucerne can also be direct drilled when there is adequate soil moisture.
Lucerne does not establish well from being sown too deep. The seed should be covered by 1-2 cm of soil. Using a roller after sowing is important to get good seed soil contact on lighter soils.
Treating lucerne seed is recommended in any instance for successful establishment. Seed teatments for lucerne include applying Rhizobia to the seed to aid nodulation of lucerne roots and Apron fungicide and Poncho® Plus insecticide are also applied to provide each plant the best possible start to establish. This is known as SowEasy Kickstart™.
Take some soil tests; A sub soil test needs to be done as well as 0-10cm sample. Sub soil sample at 20 – 60 cm to check pH and Aluminium levels at this depth. Soil Aluminium % needs to be below 2%.
Fertiliser: Olsen P minimum needs to be 12 – 15 or above (Colwell P minimum approx. 30 to 40 or higher) for a productive lucerne stand. Sowing fertiliser 100kg/ha DAP or MAP. Potassium and other major nutrients are important for lucerne, and nutrients removed in hay need to be replaced (depending on soil fertility levels).
|Nutrients removed in lucerne hay (kg nutrients per tonne of hay removed)|
|Kg removed/t hay||34.5||2.7||19.6||3.2|
Source: Australian Soil Fertility Manual p.130, J.S Glendinning,2000
Choosing the appropriate lucerne variety is a key step towards achieving a productive, persistent stand. The variety must suit the environment and the management system.
Consider the following three questions to decide on a winter activity group:
The ratio of leaf to stem in a variety is often considered important when deciding which variety to grow. Quality of lucerne hay is directly related to the amount of leaf present. Highly winter active varieties generally have a lower proportion of leaf to stem and thicker stems at maturity when compared to more dormant varieties. However, management and disease will have a much greater effect on the proportion of leaf in hay than will the variety selected.