How to support giant sunflowers?

Mine have been behaving quite nicely even though the heads must be really heavy.

They started off with a regular 6ft bamboo canes and once they reached the top board of the garage I screwed in some sturdy metal loops.

The string was supposed to be just a temporary solution until I got proper rope, but it hasn't snapped yet. The stems are quite sturdy and hard so the string is not digging into them. The plants seem to be nearly self supporting and happily sway in the winds.

The first heads will soon be ready to harvest. The biggest will be a Christmas present for our degus.

 

Will the seeds set and mature if the flower heads are cut off and dried?

The smaller side shoot flowers are full of seeds now but the dinner plate size main flowers are only slowly forming seeds starting from the outer edge. I was hoping to harvest the heads but the seed development seems quite slow now that we are having more autumn-ish weather.

Thanks!

 

And here's the illustration- the small flower is nearly full of seeds but the big one just has a ring of them on the outer rim, and the seeds are not that big yet.

The Plan is to to dry the heads off whole in a warm, sunny place (Sunderland? ).

 

A sunflower head is actually lots of single flowers just in one head.
I've noticed that the best seeds seem to be the ones around the outside, I'm guessing they are the ones that are ready and pollinated first.

So maybe the centre ones might end up smaller, but I think if the head is pretty much over and drying out they will to some extent continue drying once they are cut off.

Best to get to them before they start to rot.

 

I have found that once the 'downy' inner stuff is free to fall, it is safe to harvest the head. I agree that drying is imperative if the seed is required for resowing next year. They need to be so dry as to be resistant to a bite (They are edible!). I remove by cutting with a knife, the back of the flower head and allow to dry on a shelf in the sun. Allow a week or two. Break up and 'winnow to remove debris.
For sowing, I dust with a little sulphur and store in paper bags/envelopes. Some are planted in trays in greenhouse to produce 'shoots' during autumn/winter. Harvest when 75-100mm tall
Remainder gets fed to the great tits into winter. Do not use if mouldy- alflatoxin risk to birds. Can also be roasted and shelled for culinary use

 

An update, we have harvested the more filled heads, drying them off near the radiator.

Much appreciated by Pieni, Fourth, and Rotta (toes just seen) They'll love the biggest head we are saving for Christmas

All in all, a fun experiment for the summer.