It is crucial that farmers begin walking their paddocks and reviewing the annual tonnage of each paddock on their farms to identify paddocks for a spring reseed.
Farmers often hesitate when it comes to a spring reseed as often grass is tight and farmers are trying to save covers for the second rotation.
However, reseeding in the spring results in 10-20% more grass grown with a longer growing season, rapid growth and the grass grown is easier to preserve for silage due to higher sugar content and higher palatability and digestibility.
When it comes to reseeding and incorporating clover into the sward, establishing clover is more reliable in spring than autumn due to the stability of soil temperatures.
Less than 2% of our national grassland area is reseeded annually which needs to be addressed considering our reliance on grass silage and grazed grass.
Swards with a low perennial ryegrass content are costing farmers up to €300/ha each year due to reduced herbage production and reduced nitrogen (N) use efficiency.
Reseeding costs around €750/ha, but with the increased production in the sward, the costs will be covered in just two years making reseeding the most cost-effective on-farm investment.
Spring reseed
Farmers would want to decide which paddocks need a reseed in March or early April by walking through the field or paddock and access the sward in 10 different areas.
Farmers should analyse the swards by checking for the percentage of open ground, ryegrass and other grasses/weeds as a good pasture should have little or no open spaces, except in the case of tetraploids where space of less than 5% can be tolerated.
In an intensive system, pastures should contain ryegrass greater than 60% and many old pastures will have unsown grass species which are far less productive, and are much poorer in terms of digestibility.
The principles of reseeding are as follows:
- Aim to reseed as early as possible in April, May, or June when soil temperatures are consistent and rising and there is adequate opportunity for weed control;
- Identify paddocks that are low for phosphorus (P), potassium (K) and pH;
- Spray off old pasture with a minimum of 5L/ha of glyphosate and allow a minimum of seven to 10 days after spraying before cultivating;
- Prepare a fine, firm seedbed;
- Use grass and white clover varieties from the Teagasc Pasture Profit Index and the Department of Agriculture, Food and the Marine (DAFM) recommended list;
- Sow at a rate of 25-28kg/ha of grass plus 2.5-5.0kg/ha of medium leaved clover;
- Include no more than three or four cultivars per mix;
- Avoid sowing white clover too deep – a depth of approximately 10mm;
- Roll well to ensure good soil contact;
- Apply a suitable post-emergence spray when weeds are at seeding stage.
Many farmers saw clover perform poorly last year with a significant reduction in clover sward content seen in 2024 due to a cold summer experienced.
Clover favours warm, dry and bright growing conditions and when these deficiencies in these key meteorological factors occur, it significantly impacts the ability of clover to persist in the sward.
Clover
Many farms have started to establish clover in paddocks on their farms and should continue to do so this year despite the poor results of the legume last year. Farmers must remember that grass growth was well back last year as well.
Now is a good time if you have not already done so, to identify paddocks that may be suitable for establishing clover.
The paddocks that are suitable will be the ones that have a low weed burden and a high level of soil fertility and the legume requires soil indexes of three for P and K and it also requires a soil pH of 6.5.
These paddocks will need to be managed differently to all the other paddocks on the farm, and will need to be grazed at the correct times and grazed at lower covers to start with to allow light to reach the plant.
Having too many paddocks like this will make it difficult – if not impossible, to manage. You should aim to have it planted in roughly 15-20% of the farm.
Weather depending, from next month and into May is the ideal time to sow clover, as typically during this time, there is a combination of good sunlight and moisture available.
Waiting until June or July is not advisable as it can often be too dry and the seed won’t be able to penetrate down into the hard soil.
