Considering reseeding this year? Be aware that a spring/early summer reseed is a much better option when compared to an autumn reseed. This is in terms of annual production, growth rates and opportunities regarding weed control.
When choosing which paddocks to reseed, identify the poor-performing paddocks and those with the highest weed content or lowest perennial ryegrass content.
1. Cultivation technique
There are a number of cultivation techniques that can be used when re-seeding. All methods are equally as successful once they are completed correct.
The goal of the cultivation technique is to provide a firm seed bed for the grass seed, as a good seed to seed bed contact is essential.
2. Soil fertility
Soil fertility is a critical component of a reseed. It is the backbone for the successful establishment and production potential of the reseed.
A soil pH of 6.3 should be targeted and P and K levels should be brought up to index 3. Lime can be applied up to a rate of 7.5t/ha for a reseeded paddock.
Don’t forget that nitrogen (N) is also an important nutrient needed for the establishment of the grass plant – 40kg/ha should be applied after reseeding and then a further 40kg/ha after establishment, before the first grazing.
3. Choice of variety
The pasture profit index (PPI) can be used when choosing which grass variety to sow.
This index ranks the varieties based on components such as yield, quality, persistence and heading date. The index allows you to pick a variety based on what you want yourself or what the paddock will be used for.
For grazing paddocks, it is important to choose a variety which ranks high on both quality and yields. A mix of a tetraploid and diploid varieties will create a dense, high-quality sward.
White clover is commonly used in grazing paddocks. For good establishment, the sward should be sown at a rate of 4kg/ha or 1.5kg/ac.
4. Weed control
Chick weed and docks are the weeds most prevalent in a newly established reseed. It is important to target these weeds with the correct herbicide when they are at the seedling stage – before the first grazing – or when the grass is at the two-to-three leaf stage.
If you allow the weeds to go beyond this stage, they will be much more difficult to eradicate and may require stronger or more expensive herbicides – so timing is crucial.
More often than not, for an autumn reseed, the opportunities to get out and spray are minimal. This is one of the advantages of a spring reseed. Usually the weather is more in your favor, which allows you to spray the reseed on time.
5. Management of the reseeded sward
A newly established reseed should be managed to a high standard.
The reseeded sward should be grazed when it reaches a cover of between 800kg of DM/ha to 1,000kg of DM/ha. It should not be allowed to go above this. Grazing the sward at the correct cover will allow it to be grazed tight which will encourage it to tiller.
It should also be grazed when the weather is dry – to avoid damage to the reseed – and with young stock if possible.
Following this, graze every 17-21 days and avoid cutting for silage in the first year until the reseed has fully established.