What you do to the lawn in autumn decides how it looks in May. Three things matter most: aerate in early autumn, feed with potassium, and take the last cut once growth has stopped. The labour is RUT-eligible at 50 percent.
The last mow
Cut for the last time once the grass has stopped growing, which in central Sweden is usually some point in October.
- Aim for about four centimetres. Slightly shorter than summer height, but never scalped.
- Grass left too long flattens under snow, stays wet and invites fungal disease, particularly snow mould.
- Grass cut too short has no protection against frost.
- Do not cut wet grass, and do not cut at all after the first frost. Frozen blades tear rather than cut.
Collect the clippings this time rather than leaving them. In autumn they will not break down.
Aerating and scarifying
These are two different things and often get confused.
| What it does | When | |
|---|---|---|
| Aerating | Holes in the soil let oxygen and water reach the roots | Early autumn, or spring |
| Scarifying | Cuts through and pulls out the thatch of dead grass and moss | Preferably spring, early autumn works |
Aerating counters the compaction caused by walking, playing and mowing the same surface all summer. Compacted soil means weak roots, and weak roots mean moss.
Scarifying is harsher and the lawn needs time to recover. Done too late in autumn, the grass cannot close the wounds before winter. If in doubt, do it in spring instead.
After aerating is a good moment to top-dress with a little sand or topsoil, which improves the structure over time.
Autumn feed
Use autumn fertiliser, not the same product as in spring. The difference is what is in it:
- Spring feed is nitrogen-based and pushes fast, soft growth
- Autumn feed is potassium-rich, which hardens the grass and strengthens the roots for the cold
Feed with nitrogen in autumn and you get soft new growth just in time for it to freeze off. It is one of the most common mistakes.
Apply in September to early October, while the grass is still taking up nutrients.
Sowing grass in autumn
Late summer into early autumn is the best time of year to sow grass, which surprises people who assume it is a spring job.
- The soil is still warm, which grass needs to germinate
- Weeds are less aggressive than in spring
- There is usually enough rain without you watering
Aim for August to mid September in central Sweden. Sow in October and the grass cannot establish, and much of the seed is wasted.
Overseeding an existing lawn to fill thin patches works well straight after aerating, since the seed then reaches the soil.
Leaves and moss
Leaves must come off the lawn. A thin layer does no harm briefly, but wet leaves that pack down smother the grass and leave yellow patches and moss by spring. See leaf removal cost.
Moss is a symptom, not a disease. It grows where the grass is weak: shady, acidic, compacted or waterlogged. Removing the moss without addressing the cause means it is back next year.
Common causes and what actually helps:
| Cause | What to do |
|---|---|
| Compacted soil | Aerate, top-dress with sand |
| Shade | Prune branches, or accept shade-tolerant grass |
| Acidic pH | Lime, ideally after a soil test |
| Poor drainage | Fix the run-off, top-dress |
RUT for lawn work
RUT-eligible at 50 percent of the labour cost (Skatteverket):
- Mowing
- Aerating, watering and feeding lawns and beds
- Raking leaves
- Weeding and treating moss
- Sowing grass to restore ground after shrubs have been removed
Does not qualify:
- Laying a brand new lawn. Maintaining an existing one is RUT; creating a new one is not.
- Hauling the garden waste away
- Hiring machinery such as aerators, scarifiers and mowers
- Installing, repairing or servicing mowers, including robot mowers
The work must be done on the plot where you live. More in the RUT deduction.
Common questions
When is the last mow of the year?
Once growth has stopped, usually October. Aim for about four centimetres and never scalp it.
Should you aerate the lawn in autumn?
Yes, early autumn is the best time. It counters compaction and gets oxygen to the roots.
Which fertiliser should you use in autumn?
Potassium-rich autumn feed, not nitrogen-based spring feed. Nitrogen in autumn gives soft grass that freezes off.
Can you sow grass in autumn?
Yes, late summer to early autumn is the best time of year, since the soil is warm and weeds are less aggressive.
Does mowing and aerating qualify for RUT?
Yes, 50 percent of the labour (Skatteverket). Laying a new lawn does not.
Why does moss take over the lawn?
Moss grows where grass is weak: shade, compacted soil, acidic pH or poor drainage.
Related guides: the autumn garden cleanup, leaf removal cost and gardening services. Back to gardening in Stockholm.