The Kong Sunflower is an F1 Hybrid that is probably one of the tallest varieties you can grow. Kong is a fast growing giant sunflower that has sturdy stems that are strong enough to hold the large heads that can grow up to 40 inches in diameter.
Colour: Yellow
Height: 10′ – 14′
Heads: 1
hi, ive planted some kong f1s from seed, how long do they take till the first 2 leaves appear? and what are the ideal conditions for them? i planted some russian giants at the same time and they are 3 inches tall already.
thanks.
They should just take between 2 and 3 weeks. Some varieties can be quicker than others, they shouldn’t be much more than a weeks difference between them appearing though. Try sowing some more if they’ve not appeared yet.
I’m growing one of these in a pot in a polytunnel at the moment and its already about two foot tall after a month and a half, its leaves are growing really fast, and its stem is thickening lots, but it has little vertical growth, I was wondering when it really starts to put on some height? Does its internodes lengthen before flowering? As they are currently only about 8cm.
2 foot is not bad for the first 6 weeks. I’d expect it to kick on now though. One trick people use is to try and force height is to put it somewhere where it will get a little bit of shade to encourage it to put height on quickly to where it will get full sun.