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Rose suckers can overtake a precious rose if you don’t act early.
Sandra Ross explains how to identify and remove them.
What is an understock?
Understock is the rootstock onto which a rose is grafted or budded. A good understock will grow in a variety of soil types and offer more vigour than roses
grown from cuttings. Many roses are grafted onto ‘Dr Huey’ or Rosa multiflora. ‘Dr Huey’ is a vigorous, tough rootstock that grows well in
hot dry areas, and can be readily budded or grafted. Its flower is deep maroon with a cluster of golden stamens. Rosa multiflora is an understock
better suited to areas of higher rainfall, especially to Sydney and coastal NSW. Its flower is white. Both these understocks promote vigorous new growth,
called water shoots, growing 2-3m in a matter of weeks during summer. These should not be confused with suckers.
]What is a sucker?
A sucker is a growth that originates from the rootstock of the rose, below the bud union where the rose was grafted. With bush roses, suckers may grow
from rootstock below soil level. With standard or weeping roses, the suckers may grow from the trunk or stem of the rose. Foliage of a sucker differs
from that of the budded rose, helping with identification. Suckers grow from a point on the rootstock where there has been an injury or trauma. Digging
for weeds around a rose can cause such injury, so beware!
Why remove it?
If allowed to develop, suckers grow as long arching canes, with significantly more vigour than the rose itself. If suckers aren’t removed they will eventually
take over the rose. Flowers produced from sucker growth are not the flowers of the rose variety purchased.
How is it done?
Suckers are best removed when the soil is moist. Scrape soil back to expose the sucker. Using thick gloves and brute strength rip the sucker off. With
luck it will come off with a 'heel' (a piece of the older wood) and the point at which the sucker is removed from the rootstock will scar and 'heal'.
Suckers are more easily removed when new. If you wait until they are several years old and have had a chance to establish, it is a difficult task and
you may not succeed. Cutting the sucker off will encourage more suckers to grow.
Wild roses and some old heritage roses are not grafted but instead are grown from cuttings on their own roots. Suckers of these roses are identical to
the parent plant and can be dug up and transplanted when the rose is dormant.
Tetx: Sandra Ross