it'll "work", but you may need a bit of N supplement to get a good show of flowers, low N is best for herbs - compost would help

Bill

Those leaves, if they have been sitting around for a while, are most likely a high carbon source and mixed into the soil would most likely cause Nitrogen to be tied up as the soil bacteria digest them leaving none for your plants. Some Nitrogen supplement, at a minimum, will be needed but what else can only be determined by a good, reliable soil test.
Preferably wait at least one year befor planting anything in that bed to give the bacteria time to work.