Frost damage not forecast to be significant

Despite a couple of freezing nights, local growers don't expect there'll be much orchard damage.

Freezing temperatures the past couple of nights in some parts of the Okanagan have likely caused some damage to late cherries and early apples, but no widespread damage has been reported.

Jim Campbell, tree fruit specialist with the agriculture ministry, explained that after bloom, cherries can take temperatures as low as -2 C, and even a degree colder when there are fruitlets formed, while apple fruitlets can sustain russet damage under freezing temperatures after blossom.

However, the most susceptible period is probably over for growers in the southern part of the valley, and temperatures didn’t go that low as an Arctic front moved through the valley early this week.

Many grape varietals are in bud break now, at which point the leaves can be damaged by frost, but most vineyards set their wind machines to begin working at temperatures of -.5 C, to avoid damage that can occur at -2 C, he said.

Temperatures didn’t go that low in most areas of the valley.

At the Kelowna airport, temperatures that low were recorded in the early hours Wednesday morning, but it’s known to be in a frost pocket and measures lower temperatures than the surrounding valley.

However, cherry grower in East Kelowna, Christine Dendy said she didn’t think her orchard had sustained much damage.

She figured further north in the valley and at higher elevations around the valley there could be some damage, but not at her elevation on the benchland.

Cherries in the Kelowna area are nearly finished full bloom now, she said.

The problem is that the pollen tubes can grow in four hours when it’s 20 C, but when it’s colder out, it could take days for that tube to grow down into the pistil of the flower to pollinate. If it’s too long, it might no longer be viable by the time it gets there, she explained.

She’s confident however that blossoms pollinated last week will be fine.

Blossom time is a few days later than normal due to the cold weather this past while, she said.

However, during the summer, with enough warm days in May and June, the trees can catch up so harvest time in July is unaffected.

The forecast is for warming weather, with sunny days for the next week, and temperatures that could reach daytime highs of 29 C by Monday, according to Environment Canada.

 

jsteeves@kelownacapnews.com