Welcome to the Cake Decorators Q&A
Hi Woodysmum
An answer here may help:
Keep the cakes covered up in the fridge to prevent drying out. If you have access to a water misting bottle, fill it with simple syrup and mist the cakes once they are displayed. If they are to stand for quite a long time before serving, cover them lightly with cling film to keep the mositure in. Hope this helps.
Simple syrup is made with equal quantities of sugar and water brought to the boil for a minute without stirring. Adding a a squeeze of lemon to the liquid will prevent the syrup from forming crystals. When the ingredients come to the boil, either wash down any sugar particles down from the side of the pan with a moist pastry brush, or place the saucepan lid on to allow steam to wash down any residue. Please do not introduce a cold metal spoon to the mix as this will ‘shock’ the syrup and cause it to crystalise when it cools. The syrup can be flavoured with complimenting flavours. Good quality food flavours, a vanilla pod or alcohol can be used. If using alcohol, a reasonable amount would be 10% of the total weight of the syrup added once cool. The same syrup can be used for spraying the cakes later on. It literally is just a misting if you feel the edges of the cakes are drying. My 60th birthday cake stayed out for five hours and was still moist in the middle of one very hot July.
Don’t forget that your fillings will also keep the inside of cake moist and if you are giving a light crumb coat, that too helps to seal in the moisture. There are lots of tutorials on youtube on how to make and flavour simple syrup. I would give a link but there are too many to choose from. Hope this helps.
EDIT: Another related answer here may help too:
