Yes, you can safely start planting flowers in Spokane after Mother’s Day

Mother’s Day should be a safe time for planting flowers and gardens to avoid colds and frosts in April.

SPOKANE, Wash. – We are well into spring and have already seen a number of 70 degree days in Spokane. The weather was very nice, albeit dry, and by May, I think we’ll all be getting our gardens planted now.

But is it still too early? The short answer is now. By Mother’s Day, the second week of May, it is fairly safe to start planting without a high risk of an incoming frost.

I should make it clear that I am a meteorologist, not an experienced gardener, for the following reasons. So my thinking process is a little more analytical. Yes, we’ve already seen over 70 degrees for a few days, but it’s not the high temperatures that we need to monitor, it’s the lows.

The nights in April are just too often too cold to realistically have a head start on planting. This average rise in low temperatures rose from 34 to 40 degrees in April. In a month we can observe drastic changes in the weather not only from week to week but also from day to day.

The average last frost day in Spokane (32 degrees or lower) is April 29th! (In the last 30 years.) That means that half the time, the last frost, is before this year and half the time after. A frost in early May is therefore not uncommon. The last time it was every year from 2010 to 2013. In fact, we had a frost on May 24th in 2010, the fourth from the last recorded frost.

However, by the second week of May, the likelihood of frost decreases, which makes planting safer. But you just have to watch out for cold snaps until May, where a blanket for the freshly planted flowers will protect them at night.

A saying I’ve heard around town is that “It is safe to plant when there is no snow on Mount Spokane. At a summit of 5,886 feet, the reference point is easy to spot and the top of the mountain often has one.” certain snow depth until well into spring.

But I find waiting until there is no more snow on the mountain. Spokane is often “too sure”. Take this year as an example, the snow is melting steadily with no appreciable spring snowfall to keep the depth higher than normal, and at the highest elevations there is still a decent amount.

I’m trying to say that if you wait for the snow to completely go, you might wait a few years until mid-June.

Year after year, Spokane’s last freeze was on April 12th (for now). This would be one of the previous definitive freezes of the year.

In conclusion, April is too early and too risky to start planting, even if the afternoon is warm. But the second week of May or around Mother’s Day is a good place to start. But listen and keep an eye out for the forecast low temperatures just in case we get a late cold snap. This is a great way to protect vegetables or flowers from going under this early in the season.