I went to the second hand shop today, and bought a old sheet in green...(so it looks half decent) and have covered up, my little tree. 150 cm's high.
The leaves were getting brown and burnt, and I have another old green sheet for another tree.You can buy them from the two main thrift shops, and $4 - $5 is all you pay.Tie some string each end, as they do fly off otherwise.
For other plants that seem to be doing it hard, put a few stakes in the ground and cover again with a old green sheet.Never use white or Black.That will draw the heat, and they will still burn.
At the moment, the Earth is having a lot of solar flares, thrown at it....hence this reason for the plants, under stress.
Water your garden in very early morning...but better still about 8 pm. is a really good time for plants.They then have all night to recover.Make sure you give enough water, not just a minute here, or there.
Make sure you also water the grass, as it too needs a good helping.