i'm not familiar w/ cacti type plants. but i googled your yucca and did not find much on transplanting. however i did not spend a lot of time searching. you could google and find it's dormant time. what i suggest is moving it when it is least active in growth. dig the new hole first or prepare the container and be ready. when you do move it, do it as quick as possible and let it settle in. i did read something on google about a transplant that was not watered for a few days. usually when we transplant something we water it more frequently til it re-establishes. this may not be the case for yucca and other cacti types. i bet there is a cacti/succulent forum and they would answer you. good luck with it.

Seems to be fairly hardy in this area. If your site too windy big leaves flopping around might get tiresome or actually be torn, I suppose, although I have not seen it damaged by wind myself. Sunset WESTERN GARDEN BOOK, although rating it for south of here only (Sunset 7 and up) says "Easy to grow under all garden conditions". A garden designer I know was going to use it for pots in a formal place way out on the fringe (Issaquah or farther) some years ago. Haven't heard how it worked out, but the point is he thought it would work for that use.

I can tell you that they do transplant well. In fact, I picked up a few large clumps someone threw into garden debris outside their house. The plants didn't even have roots at the time, and it was mid Summer (rooted without any issues). Probably better to wait for milder weather and better to take as many roots as you can, but these are really survivors. Just not sure of the wisdom moving them in this continued arctic cold. Good luck!

Thank you everyone for your messages ! I am very happy to see so many options and experts opinions. gardengal48 : regarding the Oleander, this is what our neighbours already have under their window. I believe it is very old (probably 40 years) but it does not fully cover the window... Arbutus unedo: this is a lovely option, didn't think about it. Will definitely look onto it and see if I can find an already grown tree, high enough and check regarding the spreading so it won't eat too much space on the plot/shadow too much the garden (not more than the neighbours' house already do), but I find these trees pretty if well controlled! Figs/avocados: I love both fruits, and it is awesome to have trees producing fruits on the plots! we already have lemon tree, almond tree, orange tree. Our neighbours (on the other side) have fig tree, although the tree is beautiful and quite big, it is too spreaded, not so high and not so leafy unfortunately.. Avocados trees are quite random looking and I am not sure that the temperature will be ideal to grow good avocado fruits. But it would be so convenient as it is my favorite fruit ! kiminpl : thanks for the suggestions of palm trees ! We do have a Canary Island Date Palm and it is very costly as we have to pay the amount of a SIM plan to have it treated on a monthly basis due to the bugs attacks. Bismarckia nobilis + Dypsis decaryi: looks quite efficient when it comes to block the view if already grown, will check this at the tree nursery once there ! Illume Environment + Design: thanks for the name of the tree from the picture, I had no idea ^^ I think that I definitely need to check grown Yuccas at the tree nursery as I like the fact that mine is quite developed and really blocks the space it's covering. I hope to find a bigger one that might reach the height I hope for (I checked on google high Yuccas are definitely an interesting option). For the neighbours laurel, I am not quite sure it will grow much more, I read only that it could reach up to 4-5meters high in some areas in Spain and I believe that we are there already... But I will definitely take a picture and compare once I am there next April, the above picture was taken in April 2017 so it will be the occasion to see if it keeps growing ! the first picture of the very tall Yucca, this would be absolutely perfect for my needs I believe !