Can anything beat Cosmos in the cutting garden?
If there was such a thing as Desert Island plants, and there really should be shouldn’t there, then top of my list would be Cosmos, that cheery non-stop flowering annual. I grow it every year in many different forms, its the best in my opinion for cut and come again flowering in the cutting garden. It is a prolific flowerer, has delicate feathery foliage which looks lovely in a vase, it is long lasting as a cut flower and finally it’s also a great plant for the bees and other pollinators in your garden. Do I need to say any more?
They are many different cultivars of the classic annual Cosmos bipinnatus, there is the classic single flowered form, double forms, some with fluted petals and some that look like their edges have been cut with pinking shears. Some are tall and willowy and others are short and stocky. They come in a range of colours from soft pinks to white, dark pinks, almost red and then lots of breeding of new varieties has expanded the colour range with pale yellows, peachy apricots and orangey pinks. Some are bi-coloured, some have picotee coloured edges and some just seem infused with a glow. I talked about this when we introduced you to Cosmos ‘Apricotta’, its incredibly hard to describe the colour and sometimes it depends on the light but I love its peachy shades. The other Cosmos that is often grown as an annual is Cosmos sulphureus and its cultivars which are found in shades of oranges and red and again tend to be shorter and may be less useful if you are growing for cutting.
So yes, if you are growing Cosmos for cut flowers then you have to choose your cultivars carefully as some are bred more for the bedding trade and are short stubby things that wouldn’t fill your heart with joy in a vase. But fear not Higgledy Garden have done all the work for you and have selected 6 of the best. Ben love’s Cosmos. Three of them have been Higgledy stalwarts from the word go, I think it would be fair to say that one of Ben’s favourites is Cosmos ‘Purity’ you can tell that from the description! Its tall, willowy and a gorgeous clean white flower. The yellow centre is nearly always occupied by a bee in my garden. In fact they must come with a warning that you can often accidently pick them with the bee still attached and so do be careful if you then put your bucket of flowers in the car to drive home from the allotment for example! A cross bee while driving is not a happy situation to be in.
Then we have the classic Cosmos ‘Sensation’, which is a mix of pinks, some pale some dark you might get the odd white a glorious mix but again another tall variety. A jar full of mixed single flowered Cosmos is a joy to behold and just simple.
Cosmos ‘Fizzy Rose’ is a tad classier, with single or semi-double white flowers that look like their edges have been delicately dipped in a deep pink paint. The pink infusing the petals. Gorgeous.
Cosmos ‘Apricotta’ joined the range a couple of years ago after a bit of gentle nudging from me, I think it might have been more to shut me up about it than anything else but she’s been very popular. Its peachy, pink colour is very much loved in my garden and I’ve also found it to be one of the first to come in to flower. I love combining with many other colours and oddly it seems to blend well with many things.
Gemma has introduced us to Cosmos ‘Double Click Cranberries’ and we are all in love with its sumptuous rich deep red double flowers. Even though its a double, bees can still squeeze in and get to that bright yellow centre.
Finally another recommendation from me this year is Cosmos ‘Xsenia’ another curious shade, another one that has that illusive shimmer. Its pink infused with peach from the centre. Its a bit shorter than the other varieties but still as floriferous.
They are all super easy to grow and I’m not just saying that. Though its just important to know that they are half hardy annuals and will be knocked back by frosts so you have two options. Sow once the frosts have passed or sow under cover and protect them from the cold. More info can be found in the seed sowing guide. I’m lucky I have a greenhouse and I usually get them started with that protection. I just grow a few plants of each variety as I don’t have a big garden so I just sow a few seeds in a 9cm pot, cover lightly with compost and put on my windowsill till they have germinated. The other thing worth knowing is they are speedy germinators. I’d say they are probably one of the quickest annuals for germination especially if given perfect warm conditions and they don’t slow down from germination. They soon need pricking out and potting on. So just bear this in mind when you pick the time to sow as they can’t be planted out till after the last frosts, so working out when that is for your garden can be useful. I tend to plant out end of May beginning of June and start sowing them in April. But really best to grow them in the best growing conditions and if that means having a bit of patience and waiting till its warmed up a bit then thats perfectly OK, as I said later sowings will often catch up and Cosmos can be flowering from July until November. Stagger sowings to get a longer growing season for them too.
I grow mine on till they are a reasonable size so that they are good sturdy plants before I plant them out gives them a better chance against any slugs or snails that might be hanging about. There were plenty hanging around in 2024! Normally I don’t struggle with Cosmos and slugs but this year I did have a few problems early on, they particularly went for my early sowings of ‘Fizzy Rose’ and because I only grow a few of each variety they completely knocked back my first sowing but actually in the end this was no bad thing as my second sowing was fine and grew well and continued flowering until a couple of weeks ago.
They will need some support, ‘Purity’, Sensation’, ‘Fizzy Rose’ and ‘Double Click Cranberries’ especially are tall plants and quite wide. You can use netting but for these ones I tend to use thick canes and tie them in well. Another good tip is to pinch them out to encourage a bushier plant, a bushier plant simply means that it will have more flowers. When they get to about 30cm tall, they will have a number of sets of leaves up the plant by then. Pinch off the leading shoot and top set of leaves down to the next set of leaves. You will then get new shoots developing laterally from the top which means more shoots and hence more flowers.
Once Cosmos starts flowering the next important thing to remember is to keep cutting, it will keep sending out new flower stems as long as you keep cutting. If you can’t keep up with cutting for flowers at least try and keep deadheading it and then I promise you they will flower for months. For the longest vase life pick when the flower bud is just starting to open. You can use it in all sorts of ways. Here I have Cosmos ‘Apricotta’ with Larkspur ‘Misty Lavender’, Salvia ‘Oxford Blue’, Sweet pea ‘Nimbus’, white Origanum, Lysimachia barystachys and the perfect partner to Cosmos ‘Apricotta’ which is Phlox ‘Creme Brulee’.
They really are perfect partners, Cosmos ‘Apricotta’ and Phlox ‘Creme Brulee’.
Cosmos ‘Double Click Cranberries’ goes well with Cosmos ‘Apricotta’ and that other Phlox ‘Cherry Caramel’ as the pink matches the deep pink centre of the phlox flower. This arrangement also includes my favourite filler Ammi visnaga, Nicotiana ‘Starlight Dancer’ and Scabiosa ‘Magic’.
Cosmos ‘Sensation’ in a soft pink arrangement with Achillea ‘Lilac Beauty’, Ammi visnaga, Sunflower ‘Ruby Eclipse’ and Phlox ‘Creme Brulee’.
Cosmos ‘Purity’ and Cosmos ‘Apricotta’ with Aster ‘Little Carlow’, Astrantia ‘Buckland’, Phlox ‘Creme Brulee’, Phlox ‘Sugar Stars’ and Cobaea scandens. 
Don’t just keep it tucked away in a cutting garden. I visited Arley Hall in July and it had used Cosmos throughout one of the borders and it looked amazing and again as long as it is deadheaded would have flowered for months. It was used to fill gaps in a border that was full of Paeonies in the late spring and the Cosmos added lots of summer colour. This really inspired me this year to use them more throughout my garden next year.
We have Cosmos in both of our Christmas bundles this year which make great Christmas presents.
Hope you are keeping warm and safe in the wintery weather. Hope this give you some inspiration for your cutting garden next year.
Higgledy Anne
(I’m on Instagram anne_hinks if you fancy a follow, I’ve also joined Bluesky Anne Hinks)