Spring is on its way, but we have to be careful with planting for a few more weeks.

Late season hard freezes are possible in March and a cycle of freezing and thawing can damage plants. Anything not tolerant of 26 degree Fahrenheit night temperatures will require protection from freezing. The best advice for March is to take advantage of this time to do some general clean-up and pruning in anticipation of spring. 

Planting

Frost-tender Plants:
While you may be tempted by blooming plants at area greenhouses and nurseries, be aware that many of these cannot survive a hard freeze. Hold off on purchases of frost-tender plants until later in the season.
Cool Season Plants:
Cool season annuals, including pansies, petunias, snapdragons, and Iceland poppies, can be planted now if they are fully conditioned to cold growing conditions. To condition, set the plants outside but cover them for at least two weeks if temperatures go below freezing. To cover, use a frost-protecting ground cloth or an old sheet. Conditioning is necessary because plants grown in a greenhouse can suffer shock if they are planted directly into a harsh outside environment. If temperatures go too low, even conditioned cool season plants will suffer. Most pansy flowers can be damaged by temperatures below 26 degrees Fahrenheit. 
Trees and Shrubs:
New trees and shrubs are also susceptible to extreme cold during this time of year. Do not plant them in unprotected settings without mulches, staking or wind protection.

Pruning
One of the biggest questions about pruning is when to prune. Summer-blooming shrubs should be pruned now; spring-blooming shrubs should be pruned after they have bloomed. (It will not hurt a spring-blooming shrub if you prune it now, but it will mean you will not have any blooms.)

Some examples of common summer-blooming shrubs include butterfly bush, spirea, and bush clover. Examples of spring-time bloomers include forsythia, lilac, flowering dogwood and azaleas.  If in doubt, check gardening resources for details about blooming schedules.

March can also be a good time to prune most trees. The exceptions are maple, birch and elm, which already have sap running. For more information about tree pruning, check with the local extension service or an arborist.

Tom Brinda is assistant director of horticulture and education for Lewis Ginter Botanical Garden.

No comments have been posted.

Post Your Comments:

Commenting is not available in this weblog entry.