As MB would tell you, the bees only draw foundation when it is needed. Your wet spring might be adding to the slower draw-out rate, also temps need to be 60+ degrees for them to draw wax. But then again, it could be the plastic frames and foundation. I have always used wooden frames and my new swarms are drawing foundation like mad, but we have had a dry, hot spring so far. 9 of the last ten days have been 90 or higher. It also helps if you have a flow on, or are feeding them. I use only small cell wax foundation.
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