Plant ID please

[TeaAddict235]

Hello,

Could you help with this please? DS is convinced that he planted a seed but can't remember which seed. Neighbour indicated that it is a weed common in shop bought soil.

Some sort of sunflower?

According to my ID app…

It had better not be topinambur! That rampant root! I hope that it is sunflowers 🌻

Perhaps lapsana communis aka common nipplewort if not a sunflower

It does look rather like my yacon, which is a relative of Jerusalem artichoke.

Looks a bit big for nipplewort. Does look like something in the Asteraceae, leaf shape suggests Jerusalem artichoke rather than elecampane, which was the other thing I had in mind

Jerusalem artichoke is grown from tubers though, kind of like potatoes. Unusual for it to be in shop bought soil, surely?

Surely everything can grow from seed, isn't it just better for some things (quicker - more reliably like the parent plant) to grow from tubers or cuttings etc? Happy to be corrected if my assumption is wrong

Yes, jerusalem artichokes come originally from seed. They die down each winter, storing all their energy/nutrient in tubers, ready for a quick get away next spring. Each year the tubers get larger and more numerous. So normally with tuberous plants - potatoes, jerusalem artichokes, oka etc - we grow from small tubers rather than starting right at the beginning from seed. Same way as we start from onion sets rather than seed. Or plug plants.

Dragon's second point is true too - if you grow from a tuber, or a cutting, the plant will be genetically identical to the parent in every respect, none of the variability that is introduced in the seed production process.

But of course we may all be proved wrong once this thing flowers.

Sudden thought - it's not an amaranth is it?

Thank you for all of your help and suggestions. This is what happens when the DC help themselves to seeds from the shed. I'll have to post a picture once a flower blooms and take a nosey in the soil beneath.