Re-potting outdoor plants

[GreasedPiglet]

Should I re-pot outdoor plants every year? Or is every other year generally enough? I've got an acer, a bay tree, and a few herbs that have survived my middling treatment so far. Thanks!

I’m not sure when you’re supposed to do them but I usually do mine if they are out growing the pot or just start to look a bit unhealthy.

Depends on pot size and how root bound they are. When they are in big enough pots, or don’t need potting up, you could instead remove and replace the top bit of soil for fresh stuff mixed with a bit of slow release fertiliser. With the herbs you could also trim back the roots

I top dress with compost and feed.
I pot on when root bound.

With. Lot of plants there are alternatives to potting onto a larger pot. My largest Acer is one that I do not want to grow any bigger. every 3 or 4 years I take it out of the pot trim the roots by about a fifth and repot it into the same tub with fresh compost. I trim it each year.

I do the same yearly with my lavenders and my bush Clematis. The easiest way to check if a plant needs repotting is to take it out and look at the larger roots, if they are curling round the outside then repot. Even so I still trim all the roots a little bit, unwind them, shake off as much soil as possible then pot on, I do it in Autumn.

Thanks everyone, that's really helpful.