Kitchen Garden Forum

Last year, the Cosmos were like triffids and grew to 5 feet tall, despite them supposedly being the ones which grow to 30" or so.
This year, they are doing nothing much at all!.. They have barely grown since I planted them out back end of May and have had poor little flowers. I can only assume the plants got stressed out in the modules...I don't think they ever dried out...or that they decided to play a joke on me.....

Dear Elaine, maybe they are feeling a little like me and could just do with a lot less rain and bit more sunshine...

I've had similar eratic results with cosmos from year to year Elaine. One year they do what it says on the packet and another they grow like trees or are spindly weedy things but I've no idea why. I wouldn't have thought the weather could make such a difference, but you never know.

If they are weak plants but with a flower/bud I suppose pinching them out and feeding them might work for a late show, could try some for future reference.

Elaine, have you grown the same variety of cosmos? some varieties grow to about 4' but others only to about 18", so there is a great difference notwithstanding any influence by the weather.

Hello Monika. Last years' Cosmos were supposed to grow to 36" but they outgrew this by far...they were magnificent but too tall and bushy for where I'd planted them out. This year I seeded a variety which was again 36"....they are nowhere near that so far.
Nevermind, they might surprise me yet!

I lost all but five of my seedlings then the slugs eat three six inch tall plants. I nursed two more struggling seedlings back to life so now I have four plants, a different story to my first growing of Cosmos where they grew like triffids and I was crowing to everyone I met that had bought plants that Cosmos are very easy to grow from seed.

I've given up on sowing anything direct other than rocket, either slugs eat the seedlings if they germinate or weed seedlings are so prolific I give up. Even now I have established plants struggling with weeds. Cutting grass and keeping the gardens tidy on an acre with weeding leaves me little time for anything else so the weeding does take the hindmost even though I'm keen to do it.

Before getting a pack of free seeds with my KG Magazine, I had never heard of Cosmos... So I used the "Purity" seeds, thinking it would be a bit like daisies. I planted some seeds directly in the soil, and some I planted indoors... The ones in the soil did not do anything but I suspect the slugs loved the shoots. The ones started indoors, i planted out when they were around 10 centimetres high. Not knowing what they would give, i just put a few clumps here and there, thinking I would get a few strandy, leek-like flowers...

I now have these massive bushes going up to 1.5 meters. Only one has given flowers (very nice - the ones on the right - the middle white flowers are some sort of Dahlias), the others are taking their time. Can't wait for the explosion of flowers! But will re-think the front garden for next year! Thankfully they are not self seeding (I think)...

If all of them flower at once, I will post another photo!

Cosmos Purity are great. We grow some in the cut flower bit of the veg garden and they keep on and on, we have a nice vase full in the lounge at the moment. I wonder is there an equally vigorous coloured strain?

I have found Cosmos to be very vulnerable to slugs and snails, I lost some nine inch tall seedlings. All that was left was the stalk, slugs or snails had stripped the foliage but not eaten it.

Another tip, keep taking the tops of then root them in compost, they root in a couple of weeks and the case of this years batch have flowered very nicely but they became less tall.

Let the seed heads dry and save them for next year but I found many fail so you need lots of seed.

That's a good tip about rooting the bits you've taken off Richard. I'll make a note of that for next year. I'm also going to save some seed from a lovely dark red one I've grown this year and see if they grow.

Oh I love it when I can share a tip with you-lot. In fact, at the risk of milking it I'm going to let you know I grew seven plants from cuttings whilst we had a slug invasion that eat most of what I grew from seed. I have rare successes with cuttings, Cosmos is cuttings-for-learners.

Well, I'm happy to report that my ne'er do well Cosmos have really taken off and are absolutely magnificent. I too grew Purity and the other one is shades of pink, dark red and stripey ones....the white ones are lovely and I'll definitely grow them again next year. I dead head them daily and have been rewarded with non stop flowers....they are still flowering their heads off. Considering I wasn't very optimistic about them back in June, I'm very happy with them.

I bought some Aster seeds from Wilkos in their sale last back end..10p per packet and sowed them this spring...they started flowering a couple of weeks ago and they are lovely,in shades of pink, lilac and purple. I can't think why I haven't grown these before!