It has been very hot where you are they are probably going into an early autumn leaf drop. You probably haven't watered them enough, especially if they are new trees.

Thank you for your answer, but I have watered them regularly, we bought about 6 weeks ago they are about 4 foot high, at first I put them up on my deck but they were in the sun and started to get scorched so we put them down by the conservatory which is in shade from about 1pm, recently its has been quite windy. The red one has lost all of its leaves the green one has a few brown shrivled leaves. I would really appreciate any tips you could give me, do I need to repot them as they are in the original pots. Many thanks

Okay if you only bought them 6 weeks ago had them sitting in full sun and then moved them to a windy spot I'm sorry to say Darren but it is hardly surprising that they are losing their leaves. Acers need semi shade, do not like wind and as they are in pots will need a lot of water put the hose in one of the pots every evening and let trickle all night, the following evening do the second acer and then keep on watering, snag is unless you are in a soft water area you really need to use rain water - which I imagine is just about impossible. If the acers were properly potted then they should not need to be repotted right now, in fact doing so would probably kill them. Personally I would not consider buying any ornamental tree at this time of year. It has been sitting in the garden centre for months and possibly not properly cared for. Best time is spring when they have just got their new stock in.

Check the bottom of the pots - if you can see roots, they need potting up into bigger pots, and if the roots are hanging out of the pots, you will have to do it now rather than waiting till next spring. Soak the pots in a bucket first for an hour to make sure they're wet through before you try to get them out of their containers. Find a situation for them where they're out of the wind and don't get summer sun between 11 and 3 p.m.

Hi Bamboo the spring reference was to buying ornamental trees. I agree if they are pot bound can't leave without repotting but do wonder he effect this wil have on them.

If they're potbound, they'll be better off in new pots immediately than they will being left, MG. They'll be fine, the small amount of new compost involved won't contain that much food to force new growth.

Moon grower.
Thanks again for the advice, I'm very new but also very keen on gardening, will the leaves come back, can I use any sort of feed to help them, obviously I don't want to loose them.

Hi Darren the leaves wont come back this year but if you look after them they will leaf up fine in spring. I wouldn't feed now though I would put a mulch round them.

Hi Moon Grower
Feel a lot better knowing the leaves will come back as long as I look after them, what sort of mulch would you recommend. Hope you don't mind me asking all these questions but I'm only just starting with gardening and its very hard to find these sort of answers, I'm having a nightmare trying to decide what shrubs & plants to buy & where to put them I've got loads of books.
Anyway many thanks Darren

Bark would work fine as a mulch Darren.