10 Top Tips for Overseeding Turf

Did you know overseeding involves more than just sowing new grass seed between the existing grass. Proper preparation and aftercare is crucial for a good result.

The purpose of overseeding is to sow grass seed on existing turf, which after germination serves to increase the density of the grass plants which reduces the ageing process or natural decline of the turf.

This diagram on the right shows an overview of the whole process

• STEP 1: Mow grass
• STEP 2: Scarify the turf via 2 diagonal passes
• STEP 3: OVERSEED (see our top tips below)
• STEP 4: Add Top-Dressing and fertilizer
• STEP 5: Water regularly

Follow the 10 tips below and you will have your lawn or turf in great condition in time for summer…

1) TIMING

Seeding can actually be achieved at any time where the conditions allow (min temperature is required) so generally speaking any turf in the UK can seed between late February right the way through to October (some Rye grass can germinate at very cold temperatures).

2) MOW TURF SHORTER THAN NORMAL

Before you overseed remove all the cuttings after cutting
the grass really short.

3) SCARIFY

If you’re not using a scarifying machine first, make sure you use a rake to break up and remove thatch and moss from the top of the area that needs overseeding.

4) AERATE

When seeding, a solid tine (fork) can be used to a depth of 1” – 2” so that the seeds can sit in the holes which aids germination.

5) CHOOSE THE RIGHT SEED

All seeds need air, light, water and food to survive and germinate. It is actually a myth that any seed survives better than others. Bents and Fescues (that cover most of the UK) will germinate very differently to Ryegrass. If your turf has 75% Bents and/or Fescue, why seed with Ryegrass? Your turf is telling you what likes to grow, so always use this as a simple guide.

6) SEEDING RATES

Calculate the correct seed quantity for the area to be overseeded using the suppliers recommendations.

7) SEED DRESS

To protect the seeds add a thin layer of top-dressing on top of the overseeded area

which will act as a fertiliser. For the best germination results use Loam (soil with equal proportions of sand, silt and clay) for seed dressing of lawns. Its soil moisture retaining capabilities are perfect for lawns where watering will be more limited.

8) NETTING

If you don’t seed dress the treated area then covering the newly seeded area with netting or germination sheets will help to protect the seeded areas from birds.

9) WATER REGULARLY

Water as required and for a week after germination.

10) DONT USE WEED TREATMENTS SOON AFTER OVERSEEDING

Herbicides should not be used for 6-10 weeks after overseeding. Spraying before this would be a danger to the newly germinated seedlings.

Read more on the PSD Blog: Which Scarifier Set up and Why

> View the range of Overseeders on the PSD website