Sunflowers - frost hardy?

I planted mine out a couple of weeks ago John, but put a plastic bottle over them. I took it off last weekend after a week of really warm weather, and then last Saturday night we had quite a hard frost. They were still alive, but definitely not happy, so the bottle went back on!

 

Well done, mine are all still 1cm high.

 

they are listed as annuals, but they come up as herbaceous perennials, but very very hardy as they come from the USA (must be root and leaf hardy to at least -20C).. they like the sun of course. They have to be frost hardy as in their natural habitat they are at risk of frost when they emerge out of the ground as seedlings

 

I have two popping up in a front border; I certainly haven't planted them there

I grew a fair few last year and all I did was scatter the seeds and hope for the best. No bottles or TLC They grew fabulous!

 

How come the Vanilla Ices I sowed in March, and have tenderly kept warm, and preserved from rodents, have taken a month to produce 3 miserable little seedlings that look like they're going to die, while the Sinfonies I put in last week have already produced big, bonny seedlings? Maybe this is the year that I am going to produce an actual adult sunflower for the very first time.

 

I got to bring home the school rabbit at half term once.

Discovered very quickly that they are not at all Rabbit hardy.

 

And the slugs love them as well!

 

I popped mine straight into the ground, FC.
And, now is a good time to do it because the two "volunteer" sunflowers at the front of the house have just got their 2nd leaves
They do like a good drink though, so site them nearer to the water butts to save any back strain come Autumn

 

our sunflower seedlings are nowhere near big enough to plant out anytime yet, they're mere babies lol we did have a couple of slightly different looking sunflowers last year...very pretty though