Spring Pruning Flowering Shrubs and Vine

 

Pruning ornamental shrubs and vines is done to improve plant health and vigor, control size and shape, to increase flower production, as well as remove overcrowded, damaged stems and branches. Pruning should be part of the regular maintenance and upkeep of your garden. March is the right time to prune many of the shrubs and climbers in your landscape. Pruning these flowering shrubs and vines isn’t difficult if you understand these general rules. General rule number one: prune spring flowering shrubs after they bloom and before they set seed.

Spring blooming shrubs such as lilac, ninebark and weigela already have this spring's flower buds in place. These shrubs are said to bloom on “old wood” because soon after flowering last season, they began to set the buds for this season's blooms. If you prune these shrubs now, you'll remove most of the flower buds. The time to prune ornamental shrubs that flower in spring and early summer is within two weeks after they stop blooming.

General rule two: prune summer flowering shrubs such as butterfly bush, blue mist spirea and hardy hibiscus in late winter or early spring, because they bloom on this year’s growth or “new wood”. Now’s the time to prune summer flowering shrubs.

Summer flowering hardy hibiscus and butterfly bushes do best if you cut them hard to the ground now. You can use a lopper to cut the larger canes.  If you want your Blue Mist spirea to increase in size each season, prune it back by one third now.

This is also the time to prune Group 3 Clematis. These varieties bloom on new wood in late June into August. They should be cut back to a living bud at about 24" from the ground in spring just as the buds begin to swell. If you don't prune, the flowers will tend to be only up at the top of the plant and the bare stems will be unattractive below. When to prune Clematis can be tricky depending on the bloom time and variety. If you’re not sure, don’t prune.

General rule number three: Don’t prune. If you’re uncertain about the blooming habits of the shrubs and vines in your landscape, don’t prune until you’ve had time to observe each plant’s growth and bloom cycle. Then you can employ general rule one or general rule two, whichever is applicable.

General rule number four: prune anytime there is a need to remove dead, damaged or diseased branches. When it comes to the health of trees, shrubs and vines in your landscape, it’s always the right time to prune.   After you're done pruning, give your ornamental shrubs and vines a good drink. If you have questions about pruning in general or how to prune a particular shrub, stop by our Diagnostic Center. We'll help you figure out what to do to keep your shrubs and vines healthy and blooming for many seasons. 

 

 

 

 Now’s the Time to Apply Dormant Oil 

 

Dormant spraying involves applying a preventative spray in late winter while fruit trees, deciduous trees and ornamental shrubs are still dormant. The “dormant” part of “dormant oil” describes the timing of the oil’s application, rather than the type of oil.  

 

Also called horticultural oils, dormant oils are highly refined oils that act to suffocate aphids, scale, mites and other insects which seek out shelter from the winter in the bark of trees and ornamental shrubs before they hatch.  Dormant oils dry quickly, have low persistence and don’t contribute to resistance buildup.  

   

 

Dormant oil product choices include concentrated ferti-lome Dormant Spray and ready-to-use ferti-lome Horticultural Oil Spray.

Both products contain Mineral Oil. Dormant oil can be applied with a tank sprayer or a hose end sprayer.  

 

Ideal conditions for dormant spraying would be on a day in early March when the temperature will be above 40°F, there’s little or no wind and no rain or snow in the forecast. Wind will carry the oil away from the tree or shrub you’re trying to protect. You’ll want to spray early in the morning so the plant will be dry by evening. Spray enough to cover the tree or shrub thoroughly.

Whenever you decide to spray, it needs to be before the bud starts to show color.  

 

Some trees such as blue spruce and blue juniper and ornamental shrubs are sensitive to dormant oils. Stop in and check with us to make sure you're selecting the right product for the trees and shrubs in your landscape.

Spraying now with dormant oil reduces the impact over-wintering aphids, scale and other insects can have later in spring and summer.