IN THE GARDEN Expert advice

The upside of our dismal rainy summer has been an explosion in the growth rate of many pumpkin patches

One of the running food-growing stories of the summer is the mystery of the massive pumpkin plague which is invading a good part of my garden. What began as a humble planting of six Crown Prince and Queensland Blue pumpkin seedlings in November has grown into a patch covering 200sq m and still spreading. I have never seen a pumpkin patch like it. The pumpkins have become so rampant that not only have they swallowed the old pond site, rosemary hedge, plum trees and row of composting bins, they are halfway through overgrowing the poultry shed and scratch yard.

Further than that, the totally feral pumpkin explosion has now scaled the fence, gone over and begun to occupy the parkland stretching away behind the house.

Even the cricket pitch has been given up to the invader, for I have declared the Great Pumpkin Plague of 2015 a priority family research project for the summer. At the end of February, I declared not one plant was to be touched or trimmed and no part was to be harmed or removed, so at season’s end we may measure, photograph and record the final extent of the full pumpkin super spread. We might even enter it into the Guinness Book of Backyard Records!

All this means many hours have been saved stooping down to pinch out the growth tips of hundreds of scrambling runners. Normally, you would only let each runner go a distance of 3m each, before pinching out the growing tip once a fruit is set to channel all of the goodness into the fruit and not into the leaves and stalks.

For many months I had been wondering how such a ferocious growth rate of pumpkins could be fuelled and fed on a site where bare, unbroken ground was lying underneath. No part of the area occupied had been cultivated or fertilised and, apart from the first small mound of compost into which the pumpkins were planted, there was no apparent source of nutrient to support such a swathe of leaves and many dozens of fruits.

Then – one evening, late last month, as I looked up from my weeding chores and caught the sun’s late golden rays slanting down into that massive pumpkin metropolis – its secret was revealed, sparking in the light. A fine suspension of shimmering dust was rising from the yards where the Huon Blues were scratching and chasing their daily feed grain among the mixed litter. I then ran my finger across a few leaves and found the source.

The quiet north-south drift of the air down a slight slope was enough to cover the pumpkin leaves with a thin layer of nutrient-rich micro dust. This plant-feeding film was washed into the leaf pores and soil by a summer of many days of gentle rain and was driving the massive spread of the patch.

It was one of those quiet, near transcendental and totally satisfying moments of discovery that make all of the work in organic farming and food gardening worthwhile.