What to do when Juneau's spring temperatures drop?

Posted: Wednesday, March 05, 2003

Jeff Barnard called Margaret this last week and asked if we were watching the Weather Channel or looking at weather Web sites. He said there is an arctic weather front coming down that will drop the temperatures down to single digits and we should watch out.

David Lendrum is a master gardener and owner of Landscape Alaska. Responses or questions can be sent to www.landscapealaska.com.

This season is playing out much like last spring with a warm February and then a drop in temperature in March. Let's hope the whole play will not be repeated. Last year, we had a February that hovered around 45 degrees and all the shrubs and perennials were bursting out into new growth as March opened.

This season has a little more moisture so far, but let's keep an eye out for the weather in any case.

The predicted temperatures may be just a passing drift and we won't have to concern ourselves, but in the last 20 years we have seen a dozen killing springs.

The measures we take to protect our treasured specimens are simple. We water them well before the temperature drops and wrap our babies in burlap or white plastic. When the temperatures come back up, we unwrap these young plants and water them again. In most years it's not the cold that does the damage, but the water loss. The protection we give them is not to keep them warm, but to preserve their moisture rich environment.

There are thousands of plants that live with this climate, either the native species or ones that evolved in similar places. They all are able to go dormant, thicken cell fluids and harden cell walls. They shut down much of the metabolic life and wait out the winter. Many drop their leaves, which allows plants to shed those open wounds before they bleed away precious moisture.

The hemlocks that are burnt in bad winters are those along sunny beaches, not ones that are in dark canyons or sheltered from the winter sun. The same is true of our pet species. If we plant sensitive plants on the north side of our houses, where they have the protection of the building against the warming winter sun, they can go into hibernation and stay asleep until the sun gets high enough to peek over the roof. That lets them avoid the freeze and thaw cycle that is so hard on them.

We are protecting the evergreens in the nursery by laying them all down, so they will be closer to the warmth of Mother Earth and covering them with layers of plastic. A layer of white plastic, covered with a layer of clear, helps so they don't heat up during the clear sunny days. This won't stop them from getting cold, but it will keep them in a moisture rich cocoon.

The spring blooming bulbs that have poked their noses up, should get a layer of wood chips, or shredded spruce branches, or even boughs about two feet deep. This will allow them to freeze, but still be protected from the drying cold winds.

Our native species are not even greening up yet. They know that to come to life too early is a good way to win the Darwin Award. This is a prize given to those who take their genes out of the pool through an act of incredible stupidity. There is no way back after this type of mistake.

So back to the recommendations, if you have older plants, they are usually OK for a short time, if you live where it's real windy, wrap them in a tarp, don't use clear plastic. As soon as the cold front passes and it warms up, water them well.

Young plants, those planted within the last two seasons can be covered with burlap, tarps or even big boxes for the few days that the cold will be with us.

Trending this week:


© 2018. All Rights Reserved.  | Contact Us