Tuesday, February 1, 2011

Weather – Workin’ the Swing Shift by Patti O'Neal

What is a plant to do?  It is late January and all but a few plants should be peacefully enjoying the delicious dormancy of winter.  In the restful sleep of hibernation each plant sends good thoughts to its root zone where precious nutrients are stored, to be called on when the the sunshine of spring and early summer tease them to life by warming the soil and sending messages of new growth.  That’s in a perfect world.  But this year we are experiencing anything but perfect. 

Temperatures have fluctuated from 70 degrees to below 0 in a span of 3 days.  This has happened several times since December.  Then we go back up to high 40’s for a week at a time with lows only at freezing, creating a freeze thaw situation in the soil. 


When plants are subjected to this “freeze-thaw” cycle repeatedly damage can occur to the root system as plants are heaved from the ground.
  The best remedy is to apply a 3-4 inch layer of mulch around the base of your plants. This helps to mitigate the soil temperatures, thus preventing the heaving effect.  It also helps to keep moisture in the soil.   It is best to wait until after the first hard freeze to do this, and before snowfall,  so rodents do not make a comfortable home out of it.  When you apply the mulch, it is important to pull it back gently about and inch or slightly more from the crown of the plant.  This prevents excess moisture from collecting at the crown line and creating diseases and allows the plant to breathe.  Check out CSU fact sheet #7.214, Mulches for Home Grounds at www.colostate.edu.

It’s not only the roots that need protection, but  warmer days can create a situation where premature budding can occur.  This will require some above ground protection for your plants.  Be creative and cover with something that creates a layer of air between the plant and the cover to provide insulation.  It is best not to just drape sheets over plants, especially if heavy moisture is present.  The sheet will be come wet and heavy and lay directly on the leaves causing the very damage you were trying to prevent.  For plants you especially want to protect, try putting a tomato cage over it and then hanging the sheet over that, or devising something that will create the same effect.  Covers should never be left on for extended periods of time, as they can disrupt the natural transpiration of air and water in the plants.  Remove as soon as the danger has passed.

Do not be alarmed if your tulips and other bulbs are beginning to break bud.  Those that are doing so are the species varieties which are natives of China, Turkey and Asia who relish in these kinds of severe winter climates.  They will be fine. As a matter of fact, they will continue to thrive.
With all these severe temperature shifts, we have had little moisture this past month in particular.  Watering is going to be critical if you have not done any yet since you turned your irrigation system off last October, as fall was equally as dry.  So on the next day when temps are above 45 degrees, drag out the hose and deeply, slowly water trees and shrubs first and extend to herbaceous perennials if time permits.  Remember, roots go into a hard freeze more successfully deeply damp as opposed to dry.  This will prevent winter dessication injury where the plant cannot take up enough moisture to keep up with the dry, windy conditions we have been experiencing.

Do these two things now and the effort you make now will pay off in high performing, beautiful plants in the summer.