Intro to Roses
Rose bushes are in high demand and a staple in many gardens around the world because of their beautiful flowers, different growth habits (bush, shrub, climbing/rambling) and their ability to grow in a variety of different climates and soil types.
A question we often get is “Why aren’t my roses flowering?”. Under-pruning is the most common cause of unproductive rose bushes, followed by lack of fertilization and incorrect pH. Roses should be pruned annually to rejuvenate the plant by stimulating vigorous, new growth to maximize flowering.
Alongside productive flowering, roses should be pruned to correct or shape uneven growth and to remove dead or unhealthy vegetation. Roses are prone to a variety of different fungal diseases, so making sure they are pruned regularly will create a healthy environment for the plants and a less than ideal one for fungal diseases.
Here we will take you through the step by step process on how to safely and effectively prune any type of Rose.
Tools You Will Need
Heavy duty garden gloves - Many Roses have very sharp thorns on them that can damage skin.
Long Sleeves - To protect your skin from damage when working with larger plants.
Hand Pruners - These pruners are great for precision pruning smaller branches. (Make sure to disinfect with rubbing alcohol or warm soap and water before and between uses.)
Loppers - These larger pruners are for pruning thick canes that hand pruners are not strong enough to cut through. (Make sure to disinfect with rubbing alcohol or warm soap and water before and between uses.)
Types of Roses
Roses are categorized by their growth habits of shrubs, bushes or climbers/ramblers. Each type has specific needs in regards to pruning, but the overall techniques are the same. If you are unsure of the type of Rose you have, there are certain characteristics to look for in both the vegetative growth patterns and flower characteristics.
Bush (hybrid tea, grandiflora, floribundas)
Flower on new growth formed that season
Compact
Repeat-flowering
Large, clustered flowers
Shrub (Alba, Bourbon, Damask, Gallica, Moss, Portland, Provence)
Upright and spreading habits
Flower on older wood from previous seasons
Single or repeat-flowerers
Semi double or double flowers
Climbers/Ramblers (Rosa filipes)
Flower on older wood from previous seasons
Both single and repeat flowering varieties
Climb on supports
Small flushes of flowers
When to Prune
Before we dive in, find your climate zone here.
Warm Climates (Zones 9 and 10):
Roses grown in warmer climates can be lightly pruned throughout the year after each flower set to promote multiple rose flushes, followed by a harder prune every few years in the winter for flower set rejuvenation. Hard pruning can be done as early as January in these zones.
Cold Climates (Zones 3, 4, 5, 6 & 7):
Roses grown in colder climates should be pruned back hard once a year in early spring. If your plant has a lot of new growth, it can be lightly cut back before winter to protect it from harsh, winter conditions and freezing temperatures that can damage the plant. Regular, hard pruning can then be done March through May, depending on when the last frost lands.
Pruning Steps (Late winter - Early Spring)
Some pruning is done depending on the look of the flowers you are going for. Some bush roses will develop multiple flower buds on one stem. To encourage one, strong rose per stem, you would pinch off all but the top, center bud to encourage one, quality flower per stem. If you want a flush of flowers per stem, you would leave all buds intact.
Step 1: Prune Dead Flower Buds
'Deadheading' is a term used for pruning flower buds off as they die. This can be done throughout the growing season on repeat flowering varieties in warm climates. Cut to the second or third bud down the stem above a five leaf leaflet. The more leaves on a leaflet, the stronger the growth.
Pinch off multiple flower buds for better quality - Pinching off multiple buds on a flush, leaving only the center, top bud will allow for better quality roses opposed to many flowers of less quality
Step 2: Remove dead/diseased stems
Stems that are severely diseased or dead will prevent further spread of unhealthy conditions such as fungal spores and homes for insects
Step 3: Remove stems thinner than a pencil
Removing thin stems allows the plant to put its energy into thicker, healthier growth that will be more reproductive
Step 4: Remove crossing stems
Crossing stems can rub against other stems, creating wounds that are susceptible to disease and insect infestations.
Step 5: Remove Inward Growing Stems
Removing inward growing stems opens up the canopy for better air flow and light penetration
Step 6: Remove all but 3-5 canes
Leaving only the strongest, evenly spaced canes creates a strong framework
Step 7: Shorten 3-5 canes
Pruning the main canes back promotes more productive flowering and vegetative growth and protects the canes from winter conditions (shorten to 8” where cold, 10-12” where warm).
Cut to an Outward Bud The alternate buds on the stems of Roses can be used as guide points of where to cut. Cut right above a bud that is on the outside of the stem so that new stems grow outward in a V form.
Step 8: Seal Fresh Cuts
Freshly cut stems should be sealed with pruning sealer to prevent insect and disease infestations
Training Techniques
Climbing/rambling roses can be trained to grow either vertically or horizontally along features such as walls, pergolas or trees.
It is best to begin training these varieties when the stems are still young and have flexibility to them. It becomes harder to train mature stems without damaging them due to their stiff nature. Mature stems that are unable to be trained must be cut back.
When training roses vertically, side shoots should be pruned back to the main stem to direct the plant’s energy towards vertical growth.
Vertically trained roses will primarily flower at the top of the plant from a natural inhibitor that prevents the stems from growing flower buds near the bottom. This does not occur when training roses horizontally.
Garden tape or twine can be used to redirect and adhere stems to their support structures. Installing nails or pins to these structures may be necessary for permanent adherence.
Fertilizing and pH
After you have pruned your rose bushes, ensure you are fertilizing and acidifying the plant’s soil regularly. Roses are heavy nutrient feeders and if they are not getting the proper nutrients, they will have low flower yields. Fertilize with a rose specific fertilizer once a month during the growing season between April and September.
Roses like a slightly acidic soil with a pH of between 6.0 and 6.5. A soil pH meter can be used to easily determine the pH of your soil. To keep the soil acidic throughout the growing season, top dress the soil around your Rose bush with a soil acidifier in the spring and fall.
Following these pruning steps combined with the right lighting, watering and fertilizing, you should have beautiful flushes of roses year after year.
Speak with a Rose Pruning Specialist at PlantHero
If you have any more questions about how to care for your roses or you would like a specialist to walk you through pruning, we will be happy to assist you. Please click on one of the options below to book an appointment.
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