Suckers are recognizable as they occur from below the bud union or from below the ground. They appear as very strong growth with different foliage and flowers to the rest of the rose plant.
All roses purchased from Treloar's are bud grafted, meaning a variety you recieve has been grafted onto another rose known as the 'root stock'. This is usually an old fashioned type of rose and is done to add vigor and health to the variety you choose.
Suckers occur for many reasons, including roots facing upwards when the rose is planted and/or damage to the roots from digging around your rose.
Suckers appear from below the bud union where the rose was grafted, or come from below the ground next to a rose, which will then begin to grow as the original root stock. Therefore you will notice the foliage and flowers are vastly different to those of the rose that you purchased. They are very easy to mistake with water shoots (basal shoots) which grow from the bud union and grow into the new stems of the rose.
The only solution to this is to cut off the sucker at its base - this may involve digging down into the soil.
If left to grow, the sucker will completely take over the plant.
A sucker must be taken off flush with the main stem or if coming from below ground, must be followed into the soil and cut where the root is turning up, pointing the root back down.
Ensure that if the sucker is growing from below the soil that you do not just cut it off at the ground level, this multiplies the problem as three may come up where one was cut off.