The importance of clover can not be understated, especially considering how the current conflict in the Middle East is affecting fertiliser availability.

Despite the weather so far this spring, farmers may be planning reseeds for the month ahead if they can get a couple of consecutive dry days.

Aside from the weather, there is another issue with reseeding this spring, as the current fuel prices will directly impact the cost of reseeding during a time when milk is already being produced at cost of production.

But with all of that being said, investing in grass via reseeds or oversowing is still always a safe bet, as it is a fundamental part of the operation.

Clover

Teagasc recently held a webinar highlighting the key benefits and new innovations of white clover in grass-based production systems called 'Clover: The Move is On’.

During the webinar, it was highlighted that total nitrogen (N) usage averaged 313,424t over the last three years, which is a 17% reduction on the previous three years.

During the same timeframe, white clover usage increased to an average of 353t of seed, which was more than a 40% increase on the previous three years.

In 2024, a lot of farms lost confidence in clover as the weather caused issues such as striping, however farmers that stuck with it in 2025 had great success, with reduced fertiliser bills alongside improved animal performance.

According to studies, a 23% clover sward can fix approximately 70kg N/ha, while increasing milk solids/cow by 10-40kg.

White clover is mixed in with grass seed in the majority of products, however the after-management is often where clover establishment fails.

Strict management is needed in terms of soil fertility, paddock selection, and grazing protocols to ensure success with the plant.

Choosing the right product

Selecting the most suitable grass and white clover varieties for your farm is essential to ensuring success with the crop.

Trials in Moorepark, Co. Cork have shown that clover content can range between 21-29%, with the highest content found in the most grazing efficient varieties of perennial ryegrass.

That is why farmers must take the time to look through the pasture profit index (PPI) to choose a suitable variety, before going on to choose a suitable clover seed.

Teagasc grassland researcher Dr. Sarah Walsh told attendees how a clover profit index (CPI) is in the works, which will function the same as the PPI, making the process of clover selection an easier task.

As it stands, farmers can refer to the recommended varieties list below:

Choosing the right variety will boost pasture performance, and allow for graze out levels of up to 0.5cm lower.

Clover establishment

Before sowing ever begins, the paddocks need to be soil tested to ensure their fertility is sufficient for proper establishment.

You should be targeting paddocks with a soil pH of 6.5 at a minimum, with index 3-4 for phosphorus (P) and potassium (K).

Aim to sow clover during the month of April as the days will be longer and drier - however, waiting beyond April will result in conditions being too dry, with the plant not being able to establish succesfully.

Once you have the ideal conditions and fertile paddocks, sowing can begin, taking to paddocks that have been tightly grazed (below 4cm).

Farmers looking to plant clover in 2026 must use a 'two-pronged approach' for optimal clover establishment, using reseeding and oversowing in conjunction for the best result.

Teagasc has designed a five year blueprint as a guide for building clover establishment on the farm.

Each year 5-10% of the farm area should be reseeded, while a further 10-15% of the farm should be oversown each year for the five years.

Must do's when reseeding;

Spray off the old pasture with glyphosate;
Prepare a fine firm seed bed;
Apply lime, P, and K;
Sow perennial ryegrass at a rate of 27-34kg/ha;
Sow white clover at a rate of 6kg/ha;
Use a sowing depth of approx. 10-12mm;
Roll post-sowing.

Sowing deeper that 10-12mm can lead to failed germination, as the seed is quite small.

When oversowing paddocks, you must also be conscious of perennial ryegrass content and weed infestation levels, as the clover will have to fight for its place against an already established plant.

If you use a broadcasting method (fertiliser spreader), be aware that you may have varied success.

It can be difficult to get a soil/seed contact when broadcasting as the spreader is already high off the ground, and can fling the seed 6-7m across the air, which can be upset by windy conditions.

If you are using this method, Teagasc have advised that you do no more than 1ha at a time, and mix the seed through the fertiliser to avoid it sitting at the bottom of the spreader.

Stitching is one of the most common forms of oversowing.

There are a variety of machines which can be used for this process which all work equally well as long as the settings are adjusted to suit.

Fertiliser and post-sowing management

When sowing clover via a full reseed, nitrogen should be applied at a rate of 40kg N/ha at sowing.

This should be followed 4-6 weeks later by a dressing of 25kg N/ha to boost the grass/clover balance.

However, chemical N should be reduced slightly for 4-6 weeks for paddocks being oversown to ensure the newly establishing seed can compete against already established and actively growing grass.

The first grazing within oversown paddocks should take place two weeks after oversowing, or once the sward reaches 800kg DM/Ha.

For the remainder of the year, paddocks should be grazed before pre-grazing cover surpass 1,000-1,200kg DM/ha. Farmers should also continue to strive for post grazing residuals of 4cm.

If graze out levels are poor or covers get overly strong, shading will occur and the plant will struggle to get light and grow.

The same principal applies for weed infestation. If weeds such as docks, chickweed, buttercup, or redshank are present, ProClova XL should be used.

Weeds are best controlled when the grass plant is at the three leaf stage, and when the trifoliate leaf has appeared on the clover plant. However check the label to ensure you are spraying at the right time as to not hinder establishment.

When using any sprays, ensure you are in compliance with the regulations outlined in the Sustainable Use Directive.

Avoid cutting silage within the first 12 months of planting clover swards.

Once the whole farms has been reseeded, strategic oversowing and targeted reseeding will be needed to maintain clover levels.

Clover across Ireland

In the last five years, the popularity has grown significantly, helping farms reduce their N usage while maintaining production.

The following statistics have been gathered from farms within the Clover 150 programme ran by Teagasc:

One of the main setbacks on clover in Ireland is the fact that only 20% farms have optimum soil fertility.

Sub-optimal fertility levels will make it very hard to establish clover, but working toward improving soil fertility will help with nitrogen efficiency before clover is ever used.

Farmers may be thinking of using the legume as quick fix in 2026 considering fertiliser prices, however the real effect will not be seen until next spring.

Therefore they should not plant it and stop spreading fertiliser, as they will only compromise herbage production as happened in 2022 and 2023, which will ultimately cost farmers in additional concentrates fed.

Growing clover can be challenge for Irish dairy farmers who are farming on heavy soil.

Dr. Michael Egan, grassland researcher at Teagasc admitted that it is far more difficult under these circumstances, but said it is definitely possible to still have good clover content.

Another interesting topic discussed during the webinar was how grass-clover swards are outperforming multispecies in the long run, as persistence falls off in multispecies swards.