Horticulture/Rejuvenating a climbing rose
After a harsh winter, most of Rosa 'Zéphirine Drouhin' has died back, leaving two stems over 6 feet long. One has no side growth. The other is branched, but snow forced it down nearly to the ground. Thought about attaching a picture, but it would make you cry.
I'm not sure how to care for a damaged climber. Do these stems need to be cut down to the ground before new shoots will emerge from the base? I am certainly willing to sacrifice the existing growth if that will rejuvenate the plant.
I thought of layering the bent stem to produce more plants, but given what the plant has gone through, I'm not sure if this would be too much stress. I have also found conflicting information on how to layer a climbing rose. One source said to simply peel off a very thin layer of bark on the underside of buried portion of the stem.
Another said to make a cut halfway through the stem and use rooting hormone.
Another specified that the wound must be at a leaf node, but I'm sure I read somewhere about internodal rooting.
Finally, the two stems look a little different. It occurred to me one stem could be a sucker from the rootstock (I don't know if my plant is grafted). Since both stems are long and climbing (or trying to), does this mean they are both 'Zéphirine Drouhin'? I assume they don't use climbing roses for rootstock.
These Bourbon roses are grown on their own rootstock. I personally would not cut the runners back to the ground. You could cut them back halfway and root the prunings instead of throwing them away. I find they root very easily if stuck in ordinary garden soil in the shade. I just cut them into 6" pieces and stick them under a shrub - I don't turn the soil or use rooting hormone. Layering one or both runners would work, too. For that I would use loose soil, and pin them to the ground in 2 or more places - bobby pins work well for this. They will root themselves without you wounding them - which might introduce undesirable pathogens. just keep them slightly moist. Give them about 2 months to form roots. Give the main plant a light feed with some rose food.