I pull them out and they have usually seeded all over the place. always more than i need.

When you see that the seed pods have opened and the seeds have formed pull out the plants and bang the plants onto the soil to knock out the seeds and they will come again next year. That's what I do and it works for me. I have forget-me-nots everywhere each year.

I would not even bother to knock out the seed, by the time you pull them out there will be plenty on the ground.

I use a flame gun where I can to make sure that the seeds are fried along with the dratted plants. Horrible invasive weeds. They revert to the small flowered wild ones very quickly.

Just pull them out as you will find you still get them next year. If you really want to get rid pull out before they flower in about three years they have mostly gone.

I think they are cheerfull plants but pull them as soon as they look leggy. Over the years I have got white ones, pink ones and this year a pretty white one with a blue stripe. I even put up with ground elder in one place as nothing else grows there (under a hedge with rotton soil) and it looks fresh and green. This also gets yanked up after the summer. Then again I am not a precise gardener.

Ground Elder goodness! the battle I have with that, it spreads everywhere underground. I agree For-get-me-not is very pretty, but I wouldnt want it taking over my rockery either so I confine it to my woodland bit Cammomile.

Agree with the consensus above - just yank 'em all out, you'll have zillions coming up by autumn anyway, and you'll need to thin them out - big time. they're not called forget-me-not for nothing...