Due to the fact this had been a rather off the cuff, must do it right now, urge to create, make or cook something, I hadn't actually looked up any elderflower cordial recipes so I was unaware:
No.1 How many or much elderflower heads we needed
No.2 that you are supposed to collect the elderflower heads on a sunny day when their pollen is most strongly perfumed
No.3 what other ingredients are needed.
We decided that the more elderflowers the better and managed to gather a huge amount (rather too much as I discovered later) and I have say, it was almost worth it just to be able to put your nose in that basket and draw in all that beautiful scent.
When I got back home that sunday evening I got straight on t'internet and after some research discovered that I needed more sugar than I had, more lemons that I had, and some citric acid, which I didn't have any of! So back in the car for a quick trip to the co-op where I managed to get lemons, sugar, but not surprisingly they didn't have any citric acid. Not to be defeated I decided to make it anyway, citric acid or no citric acid.
If you search elderflower cordial on google lots of different recipes come up, and all of them are slightly different (amount of lemons to citric acid, and amount of time you leave the infusion to steep) but in the end I chose this one, doubled the quantity, and added the citric acid to the mixture the next day when I had managed to track some down from my local hardware shop that sells wine making stuff. (If you are looking for citric acid you might be able to get some from your pharmacy).
It made five bottles, one of which is already finished, and one now on the go and one gifted to my mother. I used two plastic bottles which I didn't sterilize, but used these first and kept them refrigerated, and three glass bottles, which I sterilized using the tips in the recipe I have linked to above.
Apart from sourcing the citric acid it was really easy to do, and apart from the boiling water and bottling it's a good recipe to make with children (Ella loved it that we made 'juice' from flowers that we picked from a tree in the hedgerow of a field, and she loves drinking the end result!)