If you planted it in the ground, have you given it enough water - it will need that till it establishes itself. Other possibility is sudden fluctuation in temperature - was the palm in a sheltered place, or under cover when you bought it, and did you put it straight outside and have some much cooler weather suddenly?

Thank you so much for your response. In ground? No, they are still in the pots that they were in when we bought them and yes, they have been watered, but not excessively. But the sudden temperature change may well be it. We bought them from a branch of E Leclerc (big French supermarket chain) and they must have been indoors in the store for 24 hours at minimum. I brought the two plants straight back to our house which is 700 metres (2100 ft) amsl. They are in pots and went straight outside, maybe 25 degrees C or more in full sun and down to maybe +5 C overnight. What (if anything) would you suggest to try to repair the damage?

Not much you can do for the leaves which have yellowed, but a bit of shelter in the night time (unless its now hot, as it is here) wouldn't come amiss for a couple of weeks till they've acclimatized themselves to being outside all the time. What you should do is leave them out for increasing periods during daylight hours over about ten days, until they're finally out all night, but I'm sure your nights will warm up soon if they haven't already, when it won't matter much anyway.

Thanks, Bamboo! You seem to have hit the nail on the head. No further yellowing since I brought the two plants undercover. They're now back outside and seem to be fine. Many Thanks for your help!

-- Richard

Glad they're better.