Monthly Archives: August 2012

Frost Affects Fruit Tree Pollination

We tend to take fruit tree pollination for granted. But it need not be so…. Apple trees with no apples? Pear trees without even a pair of pears?  Was 2012 a fruitless summer for you? Probably and the proof of this article was in the prices and origin of the fruit on the supermarket shelves.  This was a miserable year for fruit that grows on trees.  Great for soft fruits like redcurrants, but dire for topfruit like apples, pears and plums. At times it felt as if this site was pointless….

As in REALLY, TRULY, DESPERATELY bad.  Our orchard of 37 apple trees actually had 5 trees that had no fruit at all – as in none. I have never seen a season as bad as 2012.

The reasons were mainly in the weather.  We had a lovely warm February; unseasonably warm.  Plants all over the UK broke into growth as a result. The buds on the early flowering trees and plants (generally those that flower before they produce their leaves), started to swell as root systems began to pump sap in response to the warmth.  As sap rises, so flower buds force open their protective casings and the water content of soft flowering material increases.

Early March was pretty much the same and then the cold weather came. Once a plant has started into growth it cannot be reversed.  So the second half of March brought bitter cold all over Europe. Here in sunny Somerset we recorded -14C in mid-March.  Temperatures stayed low and the weather stayed dry (you will remember that there was much talk of hosepipe bans). Flower buds were mashed by the freeze and there was not enough moisture around for fruit trees to even try to repair the damage. So flowers were deformed and pollen, such as there was, sterile.

Not all of it of course, just most of it.

The weather also did terrible damage to bumble and mason bee populations – these are the pollinating workhorses of our ecosystem doing far more work than the average honeybee, but without warm hives and friendly beekeepers to feed them on unseasonable days. They emerged too early and then were frozen out.  If you think of honey bees as “busy” you should talk to a mason bee which does in a day what a honey bee can only manage in a week.

So no flowers, no pollen and no pollinators. A fruitless summer. Yuck. The blessing such as it was lay in rising water levels that were clearly critically low in March 2012. Hosepipe bans were averted and those plants that rejoice in plentiful water really partied. Watermelons anyone?