An ethical, soil-friendly answer to winter worm casts
Worm casts are back on the agenda. As soon as moisture rises and temperatures dip, casting turns smooth winter surfaces into smeared, gritty, uneven ground. It slows the pace, interferes with surface smoothness, blunts mower blades, and creates the perfect foothold for weeds and moss. Most clubs then spend the season firefighting with brushes and damage-limitation.
Alongside this, there’s a growing murmur about soil conditioners that, off the record seem to help with casts. The labels avoid mentioning worms; the mode of action isn’t clear. That’s a grey area I’m not interested in. At Bowls Central we stay on the right side of ethics and ecology: transparent, non-pesticidal, and aligned to long-term soil health.
What Downcast is (and isn’t)
Downcast is a non-pesticidal liquid that deters surface worm activity and encourages it deeper in the profile. It doesn’t kill worms; it helps keep their good work (aeration, aggregation, nutrient cycling) where it benefits the soil without spoiling the playing surface.
- Is: Ethical, soil-friendly, transparent about purpose.
- Isn’t: A pesticide, a worm “control,” or a silver bullet that replaces good practice.
Most greens see a visible reduction in surface casts within 2–3 days of application (conditions vary). That’s not a promise of perfection; it’s a practical step that takes the relentless edge off casting pressure so brushing, mowing, and moisture management can do their job.
The problem
- Playing quality: Casts smear fines across the sward, dull mower blades, and slow surfaces.
- Plant health: Smearing caps the surface, increasing surface wetness and inviting weeds and moss.
- Maintenance burden: More brushing, more abrasion, more time, usually for diminishing returns.
Downcast doesn’t hide behind euphemisms. The aim is fewer surface casts, not dead worms, done in a way that respects the soil ecosystem we’re building together and the UK Pesticide Law.
When to use it
Downcast fits naturally into the September–March window, when casting pressure is typically highest and the green surface is most vulnerable to smearing.
- Initial application (start of the casting season):
20 L/ha in 250–400 L water/ha. - Follow-ups (while pressure persists):
10 L/ha in 250–400 L water/ha every 14 days.
On sand-based rootzones or under high rainfall, shorten to ~10 days.
Quick guide for a 1500 m² bowling green (0.15 ha)
- Initial: 20 L/ha × 0.15 = 3.0 L product in 50 L water.
- Follow-up: 10 L/ha × 0.15 = 1.5 L product in 50 L water.
Application tip: Use the higher carrier volume (closer to 400 L/ha) for even coverage on fine turf.
Directions for application
- Half-fill the sprayer with clean water and start agitation.
- Add the measured Downcast dose; top up to volume.
- Apply evenly—avoid overlap stripes.
- Allow 2–3 days to see pressure reduce.
- Reapply on the interval suited to your pressure and conditions.
Compatibility: No specific tank-mix claims are made. If you plan to mix, jar-test first and trial on a small area. Keep mixes well agitated and apply promptly.
Keep the whole system honest
Downcast is one lever. The rest of the programme matters:
- Brushing: Light, regular brushing to prevent smearing; avoid aggressive abrasion on soft ground.
- Moisture management: switch or brush to re cycle dew into the soil
- Nutrition: Keep salts low and microbe-friendly; avoid forcing lush, soft growth in winter.
- Surface hygiene: Stay on top of debris; manage shade and air movement where possible.
The goal is resilient winter performance without undermining the soil biology you’ve worked to rebuild.
The ethical line
If a product’s real purpose is to kill earthworms then this is now illegal for turf application in the UK. It’s always best to stay compliant with UK pesticide legislation, honest with your players and committee, and aligned with a longer-term view of soil health. That’s been the Bowls Central way since day one.
Ready to slot Downcast into your winter plan?
- Packs: 10 L, 200 L, 1000 L
- Use window: Sept–Mar
- Results: Typically visible in 2–3 days
If you’d like me to position Downcast precisely in your current programme, send your green size, recent maintenance, and casting pressure, photos too are always helpful. Use the form on the home page to send your information and I’ll reply with a simple schedule for your site.
Transparent. Soil-friendly. Fit for purpose.