Cutting Back In Plant Maintenance. Important Items Stated
Once early flowering plants are cut down to the ground, they will re-shoot. In most cases, this means that they will produce a fresh set of leaves, giving the plant a second life as a foliage plant for the rest of the season.
Pulmonaria, for example, finish flowering in spring and, if left to their own devices, the leaves will soon become rather tatty and tired looking. If, however, they are sheared over immediately after flowering, they produce new foliage that remains fresh looking throughout the rest of the summer.
A similar thing happens with Mollis and many other plants. Some cut back plants will also have a second flowering. Once plants are dead or obviously dying, they should be cut back right down to the ground.
If plants are cut back so that stumps are left, it becomes difficult to cut next year's stems close to the ground, and so with each year that passes, the plant becomes increasingly surrounded by more, and higher, stumps.
On some plants, it is only the taller flowering stems that wilt, while the base of the plant remains green. In such cases, cut off the wilting stems only, as low as possible. Sometimes, as mentioned above, a plant may still be green but will look rather bedraggled.
Here the benefit of being cut down is that it will grow afresh. Such plants should be cut close to the ground, removing all the old growth but leaving any new foliage that might already be appearing among the old stems.
In this scenario, cutting back is mainly considered worth the effort for the new growth that appears, as this rejuvenates the plant. Sometimes, however, such new growth is required for propagation purposes.
Foe example, there is not much suitable cutting growth when violas are in full flower or once they have finished flowering, but if they are cut to the ground the new shoots are just perfect for such a purpose.
Pulmonaria, for example, finish flowering in spring and, if left to their own devices, the leaves will soon become rather tatty and tired looking. If, however, they are sheared over immediately after flowering, they produce new foliage that remains fresh looking throughout the rest of the summer.
A similar thing happens with Mollis and many other plants. Some cut back plants will also have a second flowering. Once plants are dead or obviously dying, they should be cut back right down to the ground.
If plants are cut back so that stumps are left, it becomes difficult to cut next year's stems close to the ground, and so with each year that passes, the plant becomes increasingly surrounded by more, and higher, stumps.
On some plants, it is only the taller flowering stems that wilt, while the base of the plant remains green. In such cases, cut off the wilting stems only, as low as possible. Sometimes, as mentioned above, a plant may still be green but will look rather bedraggled.
Here the benefit of being cut down is that it will grow afresh. Such plants should be cut close to the ground, removing all the old growth but leaving any new foliage that might already be appearing among the old stems.
In this scenario, cutting back is mainly considered worth the effort for the new growth that appears, as this rejuvenates the plant. Sometimes, however, such new growth is required for propagation purposes.
Foe example, there is not much suitable cutting growth when violas are in full flower or once they have finished flowering, but if they are cut to the ground the new shoots are just perfect for such a purpose.
Source...