We have had some good frosts at Beau Vista orchard in the Wairarapa New Zealand recently. This is good in killing off unwanted bugs etc in the grass and resetting bud burst of the trees. Just like apples, perry pear trees require about 600-900 hours of winter chilling hours ( these are not just frosts but hours with temperatures below about 7°C) to break dormancy and reset their spring blossom. Without enough cold, the blossoms will be sparse, delayed, or fail to open entirely - delayed foliation. And unlike apples, pears like to blossom spectacularly before the leaves appear (hysteranthous). This is a high risk evolutionary tactic to attract a lot of pollinators but puts the flower (esp. the pistils) at risk from damage from a late frost once the flower has grown out from the protective scales of the bud. (When dormant in winter they can survive temperatures as low as -25C).
#pear #winterdormancy #frost







