Overseeding: Top Tips

Overseeding into an existing old or damaged pasture can be an effective and efficient way to introduce new modern ryegrasses into a sward without the cost of a full reseed.

Increased yields and quality can be achieved without ploughing and there will also be less time out of production.

The benefits are increased DM yields, increased D values and higher crude protein, ME and sugar levels of the forage. It will also improve the disease resistance and ground cover of the sward.

There are many factors that could make overseeding unsuccessful and timing is important.

The best time to overseed is March, April, July or September as the grasses are not growing as vigorously as they are in May and June.

Overseeding: Using Harrows 

1. Soil sample to assess the pH and nutrient status of the soil and address any deficiencies.
2. Remove any excess cover by grazing hard or cutting.
3. Harrow, ideally with two or three passes if a real thick mat. This will help to remove all the dead feggy grass and weed grasses and help to create an open sward for maximum seed to soil contact.
4. Apply seed using Einbock harrows or use a fertiliser spinner.
5. Roll, with ideally a set of Cambridge rolls to get maximum seed to soil contact or put stock back in to tread the seed in for 5-7 days. Remember to take the stock out so they don’t graze out the new seedlings.
6. Do not spread nitrogen fertiliser until new seeds are well established.
7. Simulate grazing once established, pull at the grass blades with your thumb and finger. If the root system is pulled out then the plant is not ready to be grazed. If the roots stay in the ground and the grass blades rip off then you are ready to start light grazing, this could be in around 6-7 weeks from overseeding. 

Overseeding: Using Direct Drills/Slot Seeders 

1. Soil sample to assess the pH and nutrient status of the soil and address any deficiencies.
2. Remove any excess cover by grazing hard or cutting.
3. Direct drill two ways to get better ground cover and don’t drill any deeper than 1cm.
4. Roll, with ideally a set of Cambridge rolls to make sure the slot is closed or it can dry out very quickly or get waterlogged. Rolling will also ensure maximum seed to soil contact as will putting the stock back in to tread the seed in for 5-7 days. Remember to take the stock out so they don’t graze out the new seedlings.
5. Do not spread nitrogen fertiliser until new seeds are well established.
6. Simulate grazing once established, pull at the grass blades with your thumb and finger. If the root system is pulled out then the plant is not ready to be grazed. If the roots stay in the ground and the grass blades rip off then you are ready to start light grazing, this could be in around 6-7 weeks from overseeding.