how can a few weeks make such a difference?

If you can all recall I sowed some seeds a few weeks ago which hubby knocked off the windowsill meaning I had to start again with new seeds.

Those seeds I did weeks ago hardly came to anything... I planted 12 new ones last week and at a rough count (cos I'm too lazy to go through to count haha) I'd say 9 of them have sprouted already!!

Would it be the first lot of seeds just didn't sprout or is it to do with timing? Enlighten me!

 

Could be temperatures/watering - the ones you planted weeks ago could have been too hot, too cold, too wet or too dry (or a combination of these factors) at the crucial moment whereas the recent ones happened to get things just right. Maybe the first lot rotted off or dried out just as they sent out their first tiny root but you didn't realise because nothing showed.

I've sown things, had a few germinate, pricked them out, then had more of them germinate out of the original compost weeks later. Sometimes (well, mainly) plants operate to their own timetable.