Cosmos Seed collection

I've been wondering when I should be collecting my cosmos seeds. I've not dead headed it for about two or three weeks now, but before now i've been thinking arghh how do I know when to collect their seeds.

 

Today i've cracked it, as I was looking over all the dead heads I noticed a few were looking very open and very seed like. This made me think that they were ready.

 

 

I have taken pictures of a head that isn't ready and one thats open and ready.

 

Seed head not open and not ready.

 

Seed head open and ready to collect.

 

 

The seeds are the dark bits, they are fairly obvious. You can the difference between the two pictures.