cosmos summer flower arrangement

In this video, Sarah shows you how to put together a lovely roadside-inspired Cosmos 'Purity' flower arrangement.

Cosmos ‘Purity’ is a truly splendid cut flower and I often arrange it on its own because the foliage is perfect with the flower. I know that sounds ridiculous, but there aren't actually that many plants where they are just perfect together and cosmos ‘Purity’ is one of those plants. It has lovely feathery bright green leaves and beautiful white flowers, but I'm not going to arrange it on its own this time I'm going to do a proper mixed arrangement.

I have picked six different ingredients, three types of foliage and three types of flowers, and before I arrange I always split my ingredients into their groups. My first foliage plant is the most lovely thing, which I'm sure most of you know, called Ammi majus. I'm going to use what we call Molly's jug which is just a lovely little bright green milk jug and because I've got the ammi which will create a sieve, I don't actually need to use a pin holder.

I often do use a pin holder in these jars, even though they're quite small, as you never want to have any leaves below the water level - but in this case the ammi will do that for me which is why I'm just making sure to cut it down a bit. You can already see it's just such a beautiful airy plant and it can hold up the other things in the arrangement. People think ammi is just cow parsley but it's so much nicer, it's so much more delicate and it doesn't smell and it doesn’t drop - so it's in a different league.

Next what I'm going to add threaded through the ammi is this beautiful green flowered pea, which I'm obsessed with this year, Lathyrus chloranthus. I pick quite a substantial section of the vine and I love its tendril-y relaxed nature - it looks almost like you're picking a bit of the hedgerow - and then you've got these beautiful little chartreuse green flowers at the end. I'm just threading that through the ammi and you can see the ammi is holding it perfectly and that's really what the role of the primary foliage that you first put in should be. I always keep a little bit of each ingredient back as I might need them at the end.

And then light but yet denser in colour, is this beautiful red millet which is a new thing on trial this year. We've absolutely loved it; we've got it in our dahlia trial and we've got it in pots. It's incredibly easy to grow from seed and it's a really good new addition to the grass repertoire. It’s annual and it’s cut-and-come-again plant to an extent - you can pick it several times. I love that sort of airy density that it gives - if that isn't a contradiction in terms!

I've got my foliage in place now and I'm going to add my flowers. I divide the flowers and foliage into roles, so for example with the foliage I've got my primary foliage, my secondary foliage and my upper story. Similarly with the flowers, I’ve used three flowers and I've got what I call my ‘bride’, which is the Cosmos ‘Purity’, and she's the thing that the bunch is about in a way.

I've got the Cosmos ‘Purity’ cut at different heights, I don't want them all to be the same height, I want some quite proud on what I call the horizons of the arrangement and some cut shorter which are the heart. You want both a heart and a horizon in the arrangement and if you do that it looks more natural, it looks more relaxed and I think it looks prettier.

Why do you need both? Well, if you have all horizon it almost looks like it's about to fall out of the vase and if you have all heart it's just too dumpy and feels too tied in. If you have both, I think you've got the perfect balance. So, you can see this little vase is quite short but actually I'm getting some decent height in here.

Now I'm going to concentrate on the heart and hopefully you'll see what I mean by having both. It really helps to make the thing feel like a three-dimensional arrangement. The next thing I've got is Gaura ‘The Bride’ and the stamens have been seared in boiling water to make sure that they last. This is the ‘bridesmaid’. The ‘bridesmaid’ wants to be a similar colour to the ‘bride’ but not as dominant. She backs up the bride but doesn't compete with her. As a general rule, I would always pick a ‘bridesmaid’ that is a very similar colour because otherwise, if you introduce another colour at this stage, it just makes the whole thing a bit too fussy, with a bit too much going on.

Strictly speaking, we should always be turning it around so that you check its balance and I will do that at the end. Again, I'll keep one stem back of the gaura in case I need it. There’s one final thing I’m going to add into here to give it a bit of oomph, because at the moment it's quite airy and quite ethereal. I'm not going to put a colour in here, or not a strong colour that is, I'm going to put in a green and this is Nicotiana ‘Lime Green’. The point of this is that it adds a bit of contrast because I want this to be almost like a handful of the hedgerow and this lime green is perfect for it because it's got such a natural feel. Finally, I’ll revisit the few stems I kept back.

You want your arrangement to go up about twice to three times the height of the vase and you want it to come out horizontally about five or six times the size of the neck of the vase. You should end up with something that I think looks balanced and correct - beautiful but not too tidy.

So here we are with our Cosmos ‘Purity’ arrangement. Cosmos ‘Purity’ is not just on its own but is the bride; it is the centrepiece of this roadside wildflower style arrangement.