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Picked over three pounds of roadside cherries today. OH made jam. It tastes amazing but is a bit runny. Any ideas of how to improve it next time please?
If it's runny it may be that it's lacking in pectin. Cherries don't have a high pectin content.
You can improve the chances of a good set by using fruit that's not quite ripe or only just ripe (pectin content diminishes as fruit ripens). Another trick for jams using low-pectin fruit is to use some high-pectin fruit as well as your main ingredient.
Blackcurrants or redcurrants would be my suggestion to go with cherries: redcurrants to go with paler cherries and blackcurrants with dark ones.
High-pectin (easy-setting) fruit:
Blackcurrants, redcurrants, gooseberries, damsons, quinces and cooking apples.
or use 'jam sugar' which contains pectin and helps low pectin fruit jams to set