Cold Temperatures

Dunedin has had some pretty rough weather recently. But cold weather is absolutely necessary for many plants, as flowering and fruiting is more prolific after they have experienced a certain amount of accumulated cold weather, termed winter chilling. Not enough cold can result in poor flowering or fruiting and weak growth.

The need for a period of winter chill is common in many fruit trees, berries, most deciduous plants, spring bulbs and ornamental plants from temperate climates. They love winter and a period of dormancy allows them to rest, recharge, and reset their internal functions.

This process is variously called vernalisation, cold stratification or chill hours. It is essentially the total number of days, at or below 0° to 7°C that an area consistently receives each winter. Not enough cold, or not long enough a period of cold weather means the tree or shrub won’t be stimulated to flower well and no flowers means no fruit.

Winter temperatures are also a powerful ally in the fight against a wide range of garden pests and diseases, reducing their levels before spring growth takes off, giving the plant a head start.

So we need to be thankful for winter cold.

Extreme cold can still threaten the survival of young or sensitive plants. The blog -https://www.yourneighboursgarden.co.nz/post/more-on-protecting-plants-from-cold-weather gives some hints on protecting favourite plants during cold periods.

And there are signs around the city that spring is on the way. The days are getting longer which makes most people feel like coming out of hibernation. Early flowering spring bulbs can be seen around and about. Magnolias are beginning to bloom. And there are wafts of floral fragrance from Daphnes.