Making blackberry and lemon verbena jam

After the blackberries are mashed, sugar and lemon juice are stirred in. Then the fruit mix is poured into a large pan with the verbena leaves in a cheescloth bag tied to its side. The bag is submerged into the jam mix.  (Barbara Davidson / Los Angeles Times)

Berry jams produce a bit of foam that needs to be skimmed during cooking. The foam doesn’t harm the jam, but it can make it muddy.   (Barbara Davidson / Los Angeles Times)

After the jam tests done, it should be canned quickly. Recipe: Blackberry and lemon verbena jam   (Barbara Davidson / Los Angeles Times)

Various jams are for sale at Sqirl. Recipe: Blackberry and lemon verbena jam   (Barbara Davidson / Los Angeles Times)