I've replanted/stolen/adopted about 3 kinds of weeds (mostly lawn-type grasses but wait for the pictures) from in front of my building.
The soil down there is hardly anything more than buildings' rubble with some sand blown over by the wind. What I replant into is freshly purchased fertilized soil in an (I believe a large enough) pot.
The temperature outside goes down to about -10°C at night; where I've placed them it goes down to zero or so. The noon high is about +15°C. The temperature during all the replanting was at the top end of the stated range, perhaps 10°C outside / +5 at the destination. But zero frost anywhere.
Watering and light - have been exactly as for my houseplants (who are quite happy). Water 2/week; several hours of direct sun but not all day.
Digging out all the roots without destroying the finest of them - is IMHO basically impossible, but I've used methods that have worked well in other situations.
Still they all died. pictures soon Why?