I have not yet heard anyone mention that the Apistan strips should be
removed BEFORE the time that a typical vegetable garden is in bloom.
if you leave Apistan in all year YOU will be partially responsible for
helping to develope  RESISTANT mites!! the whole point is that the Apistan
knock the mite level down to a level below the damage threshold.  removal
of the pesticide is crucial to prevent the genetic selection of  resistant
mites.  there has been a lot of good research on this latey.  unfortunately
most of the findings are published in journals that are not popular amongst
most beekeepers.
leaving Apistan in all year is lazy and irresponsible!
anyone remember Integrated Pest Management???