A common problem with lemon trees and other grafted citrus trees are suckers. Here we are talking about new growth from below the graft. They are easy to remove and should be delta with as soon as they appear.
It is easy to identify the suckers as not only are they from below the graft, the foliage is usually very different as well.
Causes of suckers on citrus trees
Grafted citrus trees are one type grafted onto or growing on a different rootstock. This is done to produce hardier, disease resistant or dwarf type trees.
The suckers that appear from below the graft are shoots of the rootstock and should be removed as this growth can ‘take over’ the tree.
Suckers will occur from time to time, however on cause is damage to the trunk below the graft by mowing etc.
Pictured we have a classic example of a citrus tree (Grafted Meyer lemon tree) with suckers growing below the graft. These were caused by line trimmer damage to the trunk of the tree.
How to remove the suckers
Simply cut them back flush with the trunk with a sharp pair of loppers or a knife. Try to avoid damaging the trunk any further.
You can also remove them by hand when the suckers are small, simply rub them off, many gardeners believe that this is the best method.