Kitchen Garden Forum

Have noticed a lot of tiny self sown seedlings from my Cosmos flowers appearing in my border, probably due to the late sunshine.
Is there any point in me trying to overwinter them in my plastic greenhouse or would I simply be wasting my time?

I think I would, just to see if they survive. Although I keep reading about the ghastly cold winter that is threatening to arrive so unless your greenhouse is heated, they're probably doomed. I always try to save seedlings as i feel too guilty to just chuck them in the compost. I often see tomato seedlings appearing in my greenhouse in the autumn and they're still there in the spring, even though my greenhouse has a cracked window pane which lets the draught in and is unheated.

Give it a try, Primrose, after all you have not lost anything if they don't survive. I have just potter up a whole lot of calendula and cerinthe seedlings for the same reason.

Dear Primrose,
Cosmos are half hardy annuals; this means that they will not generally stand frost or temperatures below about 5C. Calendula and Cerinthe are hardy annuals and will stand some frost and often overwinter without protection (but are best potted and tucked into a cold frame).

Keeping Cosmos overwinter will involve a lot of pinching to stop them becoming leggy and under cover in low light levels they are prone to mildew. Where there are some sprouting now there will probably be more seeds waiting for next spring and I would just give the area a light mulch to hide the seeds and hope for great things next spring.

Regards Sally Wright

Cosmos are tender annuals, and will quickly turn brown when temperatures drop below freezing.

Sally Wright, what were you doing up at 3.10am?

We've got cerinthe seedlings coming up all over the rockery about 10 yards from the plants, I think something must like the big seeds and has been hiding them away.

Cerinthe seed themselves exceedingly well - I have them coming up in my lawn - in little cracks in the paving and other peculiar places. I don't know why they're so expensive to buy in seed packets - they grow like weeds in my garden (beautiful weeds though). The bees love them and I try to transplant the naughty ones to more suitable places.

It's like Mexican fleabane (Erigeron karvinskianus), isn't it? A pot of these costs at least a fiver whereas they seed themselves all over the place, especially in any paving cracks and gravel. And they are completely hardy.

Dear Gerry,
I couldn't sleep; simple as that.
regards Sally Wright.

Sally, have you had OF issues?
You now have two logins to KG?