certainly 2 weeks + for me. I don't know how big are your patches, but I have trouble with the wood pigeons eating the seeds which is why I've had failures. I put down some seed for my neighbour and an hour later two pigeons were at it! I cover with fleece or bubble wrap, keeps the pigeons off and probably raises the temp a bit too. keep watering though
I've sprinkled three boxes of seeds over the bare patches now. Still no grass but 6 very fat wood pigeons are regular visitors. Too many patches to fleece and net them all, and the dog, who is responsible for the patches, is too old and lazy to chase them anymore 😡
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