When to Prune

 

When and how to prune each shrub or bush can be difficult to navigate. Here are a number of lists of when it is best to prune.

 

Pruning Times for Flowering Shrubs

 

Prune in Early Spring or when Dormant Prune After Flowering

Beautyberry Barberry

Broom Beautybush

Butterfly Bush Butterfly Bush

Cotoneaster Daphne

Dogwood Elder

Euonymus Flowering Almond

False Spirea Forsythia

Hibiscus Honeysuckle

Hydrangea Kerria

Potentilla Lilac

Snowberry Magnolia

Sorbaria Ninebark

Spirea that bloom in summer Purple Leaf Sandcherry

Smoke Bush

Spring Flowering Spirea, Bridal Wreath

Viburnum

Weigela

 

Pruning Vines

Group 1 Clematis

(Flowers on previous seasons growth, prune all dead and weak stems immediately after flowering)

Alpina Constance Macropetala Pauline

Alpina Helsingborg Macropetala Rosy O’Grady

Alpina Pink Flamingo Montana Freda

Alpina Willy Montana Grandiflora

Macropetala Blue Bird Montana Pink Perfection

Macropetala Jan Lindmark Montana Rubens

Marcopetala Markham’s Pink Montana Tetrarose

 

Group 2 Clematis

(Flowers on previous season’s growth in May to June, and again in September on the currents season’s growth; prune late winter/early spring, removing dead leaves at each stage of pruning)

Alabast Ken Donson

Anna Louise Lemon Chiffon

Arctic Queen Liberationi

Asao Lincoln Star

Bees Jubilee Louise Rowe

Blue Ravine Marie Biosselot

Carnaby Miss Bateman

Countess of Lovelace Multi-Blue

Dr. Ruppel Nelly Moser

Duchess of Edinburgh Niobe

Elsa Spath Pink Champagne

General Sikorski Royalty

Gillian Blades Ruby Glow

Guernsey Cream Snow Queen

Guiding Star The President

Henryi Josephine

 

Group 3 Clematis

(Flowers on current season’s growth; prune late winter/early spring; remove dead leaves at each stage of pruning)

Blue Angel Rhapsody

Comtesse De Bouchard Rouge Cardinal

Ernest Markham Tangutica

Florida Plena Terniflora

Gypsy Queen Texensis

Hagley Hybrid Ville De Lyon

Jackmanii Viticella Carmencita

Jackmanii Superba Viticella Etoile Violette

Lilancina Floribunda Viticella Madame Julia Correvon

Madam Baron Veillard Viticella Polish Spirit

Madam Edouard Andre Viticella Purpurea Plena

Perle D’Azure Viticella Purpurea Plena Elegans

Pink Fantasy

Other Vines

Bittersweet	Need male and female to produce	Prune only to keep suckers under control
Five-leaf Akebia		Cut back heavy each winter
Honeysuckle	Good for shady areas.	Prune heavily during the summer, thin out vines and remove suckers after blooming.
Wisteria	Questionable in Ottawa’s climate	Prune in spring and again late summer
Silver Lace Vine	Very fast growing.	Prune when dormant
Boston Ivy	Red fall colour	Prune Anytime
Virginia Creeper	Very Hardy, red fall colour	Prune Anytime
Climbing Hydrangea	Excellent for shady areas	Prune in Early Spring
Ivy	Excellent ground covers as well as vines	Prune Anytime
Trumpet Vine	Available in yellow, red and orange	Prune after flowers and to keep from being too heavy

 

Pruning Fruit Trees

Apples, Cherries and Pears

The best time to prune the fruit trees are in the late winter. The main reasons for this is that there is a good chance that you will get winter die back and with this being a real possibility it is best to do your pruning after this has happened. The tree should be dormant so as to minimize the possibility of losing a lot of sap from bleeding. This is the general rule if you are doing regular and routine pruning.

If you are doing major cutting and reshaping, this should be done in fall so as to not stimulate too much new growth in the early spring. Once the tree is reshaped properly you may then go back to pruning in the late winter while the tree is dormant.

 

Shade Trees

Description	Type of Pruning	Time of Pruning
Ash	Prune lower limbs, otherwise minimal pruning is needed	Fall
Birch	Prune to train when young, and to show off bark	Late Summer, Early Fall
Crabapple	Follow recommendations for apples	Late Winter
Ginkgo	Basal pruning only to emphasize tree’s height, as little as possible	Fall
Honey locust	Try to prune to a strong central leader as much as possible	Late Summer
Horse Chestnut	Prune off lower limbs or damaged limbs as need be	Late Summer
Lilac	Prune after flowering	Early to Late Summer
Linden		Late Summer
Maple	Prune out dead wood and to shape.	Late Summer, Never in Late Winter or Spring
Oak	Prune out dead, diseased, and broken wood.	Late Summer

 

Pruning Evergreens

Creeping Junipers	Snip out outer ends and dead branches	Spring and Summer, not past late August
Cedars	Regular sheering	Sheer several times a growing season, not during extreme drought or stress
Euonymus	Trim out dead and to shape	Throughout growing season, not during extreme drought or stress
Pine & Spruce	Shear as needed to maintain level of thickness wanted.	If the tree is large enough, let candles grow to one inch then clip them off completely, otherwise let them grow to 2-4” long, and pinch off the end.
Upright Junipers	Shear to shape as need be	Throughout the growing season, not during extreme drought or stress

Pruning Perennials

Deadheading

It is very beneficial to deadhead your perennials so as to encourage more blooming. If you allow dead flowers to move on to seed pods, the plant stops producing flowers, whereas if you deadhead the seed pods, the perennials automatically pushes more blooms.

 

Over-wintering

Cut your perennials back after the first frost to 3” above the ground to allow for easier disease control and a cleaner garden. It is always wise to mulch your perennials before winter to help insulate them against a hard winter.

 

Pruning Annuals

Deadheading

Much like perennials, but more importantly, annuals should be deadheaded as soon as the flowers start to end. This will help to encourage a fuller plant.

 

Thickening up

Annuals will also benefit from pinching and trimming to help thicken them up. If allowed to grow too tall at times, some will become spindly. By pinching the plant back, a stockier, heavier plant can be developed.