Rose Pruning in Winter

Roses go into hibernation in winter which is when they stop producing new growth and lose all their old leaves but in WA, the weather doesn’t always get quite cold enough so it’s best to wait until the end of July or the first week of August before getting pruning underway.  This will mean that their new growth will develop when the weather is slightly warm and so there will be less chance of them developing black spot early in the season.

Roses are pruned for four main reasons:

• To encourage new growth and flowers.
• To remove dead and diseased wood.
• To improve air circulation around the bush which reduces the incidence of pest and diseases.
• To shape the plant.

When preparing to prune, sharpen the secateurs so that they make a nice clean cut and this will help reduce diseases on the stem.  Also have a spray bottle handy which has a solution of 10mL bleach to 1L water which you can use to disinfect your secateurs in between each bush – this will help stop the transfer of diseases from one to the other.  Finally, have a spray bottle with lime sulfur in it, prepared as per the directions.

Lime sulfur is an organic product that is essential in the rose pruning process.  After each plant is pruned, lime sulfur is sprayed onto the branches to ‘run off stage’ which simply means that it is well and truly coated to the point where the liquid is dribbling down the bush.  This makes sure that the lime sulfur gets in to all the crevices in the stems and nodes and deals with any pests, such as scale, as well as bacteria that might develop into diseases.  Never prune a rose without using lime sulfur as it is the best way to ensure a healthy rose through the growing season.

Pruning a rose is actually not all that hard and the thing to remember is that it is better to prune it badly than not to prune it at all.  And, remember that they really do need a good hard cut in winter so a great recommendation is to prune when you are angry.  That way, you will do a darn good job and you will feel better for it afterwards as well!

 

PRUNING NEW ROSES
An exception to the rule is with new roses.  In the first two years, prune only to remove dead or diseased stems or those that are rubbing together to give the bush the chance to develop.  And, as much as you might not want to, during the first season of producing flower buds, remove them to promote new growth of the bush.  This will pay dividends down the track.

 

PRUNING BUSH ROSES
Floribunda, Hybrid Teas and Grandiflora all produce flowers on new wood so a hard prune in early spring will encourage new wood to grow and a lot more more flowers.    Hybrid teas can be cut back to about 40cm from the ground and floribunda to about 30cm.

1. Start by cutting off the top third.  This helps to make the bush more manageable and allows you to see what is going on inside.
2. Remove any old canes and those that are dead, diseased or damaged.
3. Cut out any twiggy growth that is less than a pencil thickness.
4. Take out any stems that are growing inwards.  This helps to create a vase shape and helps improve air circulation and the light getting in later on.
5. Reduce thick, strong stems by about half their height.  Thinner canes can be cut back to a third as this will encourage them to grow stronger.
6. Cut out suckers below the soil level.  These are the very tough, long branches that appear from the very base of the rose bush or sometimes from the ground a few centimetres away.  These are incredibly vigorous and come from the roots that have been grafter on.  If they are allowed to establish, they will take over and the rest of the rose will become weak and there will only be small, underwhelming flowers.

Pruning bush roses to form a vase shape which will encourage new growth and more blooms.

 

 

PRUNING CLIMBING ROSES
Climbing roses have long thick canes that all come from a fairly short base.  They are often trained against a flat wall or over an arch.  Pruning these is completely different to pruning a bush rose as if the canes are cut off as drastically as they are on a bush rose, there will be no climbing habit at all.

Flowers form at the very top of the canes of a climbing rose so, if the canes are allowed to climb straight up to the sky, the flowers will be right at the very top of the cane and there will be none lower down.  So, we trick the rose into thinking that it has lots of top points by making the cane run horizontally along the wall.  That way, every node that runs along the cane is a ‘top point’ and will produce a flower.  Take a look at the diagram below to see an example of how the branches are tied horizontally.

1. Let young climbing canes grow to the sky in their first spring and summer then in autumn, gently weigh them down so that they are horizontal and tie them down.
2. Don’t allow canes to head downhill as this will cause them to have one higher point which will be the only places that the flowers form.
3. From the third year, cut about a third off the oldest canes to encourage new growth to develop from the base and then each year after that, remove a few of the very oldest canes trying to encourage new ones to establish.
4. Cut the side shoots that run along the cane down to the second or third bud.
5. The tips can be cut off long canes to keep the bush to the correct size.

Pruning long canes of climbing roses so that they are horizontal to form new flowers.

 

 

PRUNING STANDARD ROSES
Standard roses are created by grafting a selected rose onto a clear stem and so they have to be pruned according to the variety on the top.

1. Dead-head and trim any wayward growth regularly to maintain a tidy habit.
2. In the first couple of years, prune only to remove dead or diseased wood and any branches that cross and are damaged by rubbing.
3. Remove suckers that are growing from beneath the graft for from the base of the plant.  If possible, pull them down and off instead of cutting them as this is a more permanent solution.
4. Then prune as you would a bush rose, cutting back hard to keep the ‘bush’ standard on the top.
5. If the bush is lop-sided, prune harder on the smaller side to encourage more vigorous growth.  It sounds weird but, because pruning causes roses to grow more vigorously, pruning the smaller side more will make it grow faster.

Prune standard roses according to the bush that has been grafted on the top.