MINNEAPOLIS - Many gardeners have questions about what is going to happen when spring rolls around. The lack of snow to protect the plants along with the lack of moisture is really concerning all of the green thumbs out there. The mild temperatures are also something to be concerned with when it comes to pests and how they fared through the winter.
I spoke with University of Minnesota entomologist Jeffrey Hahn who said there are many factors in play when it comes to what the bug picture will be like in the spring. Hahn doesn't think the warm temperatures have played a huge part but that most bugs probably overwintered quite well. He is doing research on the threshold that would kill Emerald Ash Borer as they overwinter in ash trees. He has found that the threshold seems to be around -30 degrees. Temperatures haven't been anywhere close to that here in the Twin Cities.
Japanese beetles overwinter as grubs in the ground. He thinks that the lack of snow might affect them if they do not go deep enough since we did have some cold nights with bare ground. It really depends on what your area was like in late July when they were laying the eggs. If your ground was parched, the chances that they couldn't get very deep because of hard soil could play in to their survival. Time will tell.
I also spoke with turf specialist from the U of M Brian Horgan and he thinks the drought could affect some lawns. This is what he said:
"The concern with lawns relates to the dry fall and lack of snow. Although temperatures have been moderate this winter, plant dessication can occur. That is the primary concern. Other types of winter turf injuries include crown hydration, low temperature kill and anoxia. We are not concerned about these at this point of time.
To determine the extent of damage that we may be experiencing in the spring, we take plant samples from the field and see if they grow when placed in the greenhouse. To date, we see no issues. Plants are growing fine when given a little water with warm soils.
We certainly can define scenarios from which this could change, however I don't see a lot of value in going through those scenarios at this point.
If the droughty conditions persist into the spring, homeowners will want to turn on that sprinkler a little earlier than they are use to.
Best case; winter ends, the soil thaws and we get frequent spring rains to recharge the soil and wake up our plants (grass)."
So it's a bit of a waiting game but it is good information to know as you dream of spring!
Belinda & Bobby