Green butter cream

ps when I made the football pitch I put on chocolate buttercream (mud) and sprinkled the green coconut grass on top.

ps the Tesco one has E numbers which do not look alarming but the colour itself appears to come from spirulina (an algae).

You can buy coloured fondant icing or mix green food colouring into a block of white icing then perhaps grate it through a fine grater?

I used desiccated coconut and green food colouring as well for a football pitch cake.
Trying to remember what DD did last year for DGS's cake

Found it in the cupboard: Tesco green food colouring, probably she used it in buttercream. If you can find the palest butter it would be best.

I saw this too:
Coconut is not a botanical nut; it is classified as a fruit, even though the Food and Drug Administration recognizes coconut as a tree nut. While allergic reactions to coconut have been documented, most people who are allergic to tree nuts can safely eat coconut

Dandelion leaves an alternative to spinach

Andy I looked at their website and I will go and have a good mooch round one day! I didn't know they were there.

Greyduster world of icing is on West Bars. Not as central as cake craft. My daughter in law always uses them (probably because she can park outside). I'm sure cake craft are just as good though, I'd forgotten about that shop. Good luck with the cake.

Andyf, Cake Craft, near the bus station. I was in there last week buying bits and pieces. Where is World of Icing?

Izabella that sounds like a good idea (no E numbers either!) if I could get some spinach but at the moment no-one seems to have any! DD will have to have her salmon and spinach croute sans spinach for lunch today!

Shysal they sell that at Cake Craft. I wish I'd known I was going to need some when I was there last week. Hindsight is a wonderful thing!

Lots of good suggestions to go at; thank you all.

Lightly steam spinach. Squeeze. Add the juice for a deep colour.

Concentrated food colouring paste is the answer. This company on Ebay will get some to you by Tuesday 7th.
An alternative method of producing grass is to buy some green fondant icing and press it through a sieve to make the blades.
www.ebay.co.uk/itm/Sugarflair-Maximum-Concentrated-Paste-Edible-Food-Colouring-Cake-Decorating-/122324878279?var=422811979267&hash=item1c7b2183c7:g:ieAAAOSwnHZYh0Dv

*Greyduster, are you going to World of icing in Chesterfield? I'm sure they will have good advice.

www.lakeland.co.uk/17519/8-Wilton®-Icing-Colours

Same thing I think Grey

Sorry, N&G I didn't see your post. I'll have a look at the Lakeland colours.

Thanks for responding, ladies. mcem I thought about coconut, but was a bit nervous about nut allergies among the boys who are coming to his party. If it was just for us I wouldn't worry. It would make things a whole lot easier. tanith no matter what proportions I mix the food colour, I can't get past the peppermint colour. hilda that looks like the colour and effect I am trying to achieve so if I try has to be Wiltons I will have to make a trip into Chesterfield because there is nowhere nearer I can get it. Whoever said this was going to be simple!

I use the colours from Lake land and find they're pretty good ( but I like the coconut idea mcem)

When putting 'grass' on a cake I found that rubbing green food colouring into dessicated coconut was pretty effective both for colour and texture. Scatter onto a layer of butter icing and press gently into place.

Here's a mumsnet discussion about just such a problem. have a read

Make the icing a little thicker than normal and then I would add the blue first then very small drops of yellow till the colour was as I wanted it. Apologies if that's what you already tried?