Gardening Shrubs – Conserving Plant Energy

Certain common shrubs, especially some evergreens, require no more by way of pruning than the removal of dead flower heads. Flower heads are best removed after blooming because a lot of the plant’s energy goes into the making of seeds. Once we remove the flower heads, this plant energy is saved and it will mean a larger number of flowers in the following year.

With rhododendrons and azaleas, the clusters of seed pods can be twisted off the plant, taking care not to damage the buds which are developing below. Old flower heads of lilacs can be removed with a sharp pair of secateurs, cutting them off at the base. Heather and lavender require only a light trim with a pair of shears after they have flowered.

This also keeps the plants compact. Care has to be taken that only the flower heads are removed and the main shoot or stem are not cut or nicked.

Flowers that bloom in winter can be left till March or April before they are trimmed. Shrubs which have been budded or grafted onto a rootstock invariably throw up suckers. The plants that fall in this category include rhododendrons, azaleas and lilacs. Suckers can be removed by cutting them at their point of origin. Suckers are easily identifiable as the leaves are usually slightly different from those of the main growth. It is necessary to be alert to the presence of dead or diseased wood.

These are very easily infected, besides, of course, being unsightly. Dead or diseased wood should be cut off immediately. Shrub roses too have to be checked for dead wood. If you feel the bushes are becoming too thick, then a little of the old wood could be pruned. Apart from this, shrub roses do not need much attention.

If you want to grow more of your favorite plants from the seeds, then you cannot remove the flower heads. You will need the flowers to make the seeds. For example, flowers like the Clematis, Lunaria, and Pyracantha are not removed. Instead the seeds are collected for planting in the next season.

The flower bearing stems of the Lupin when cut back to the base soon after it has flowered will flower again later with another flush of flowers. Delphiniums, Phlox, Roses and Dianthus are some other flowers which flower again lusciously and for longer periods of time if the dead flower heads are removed.