Planting | Aftercare
Many kinds of perennial flowers need practically no maintenance. However, some kinds do and it is wise to choose carefully. Perennial flowers come up year after year, unlike bedding plants that must be planted each year. This is a big saving of effort; the more garden space given over to perennial flowers instead of annuals, the better.
Even though they grow out each year, these non-woody plants die down at the end of each season. Effectively therefore, they are self-pruning. Perennial flowers are very quick to get established, requiring little watering, and some kinds are very good at competing with weeds. With each passing year, the original plant spreads outwards to form a clump and claim more ground for itself. This is ground denied to weeds.
Unlike trees and shrubs which can be planted into dead sod, it is best for perennial flowers to have the soil dug over and cultivated before planting. But it is possible to plant into dead sod too. It is essential to get these plants off to a good start. Otherwise, their ability to compete with weeds will be much reduced.
For the first two or three years, it is worth dividing and re-planting the original plants, such the candelabra primulas shown. This technique, which initially requires more effort, results in a quicker filling-in of the ground area and subsequently reduces the work of weed control.
The achieveing of complete control of perennial weeds before planting perennial flowers will save endless effort later. There is no possibility of using weed killers once the perennial flowers have been planted, and control of perennial weeds will become extremely difficult and time-consuming.
At least two applications of Roundup or similar will be necessary to kill off all existing vegetation. If chemical control is ruled out, meticulous digging up of the roots of perennial weeds, though not wholly effective, is one way to remove perennial weeds in advance of planting.
Alternatively, old carpet or plastic sheeting laid over the ground for about twelve months provides a relatively easy and effective, if slow, method of control.
Weed control following establishment is made more easy by selecting perennial flowers that cover the soil surface. The less soil left bare, the fewer weeds come through. Hoeing is relatively easy if the weeds are not allowed to grow taller than 5 centimetres and certainly never allowed to go to seed.
Hand-weeding is much slower but will probably be necessary close to the plants. A mulch of bark chippings is very effective around perennial flowers, especially in the early years until the plants begin to cover the soil.
Perennial flowers need relatively little regular care and attention. They need far less effort than annual flowers and roses, for example. In fact, if some care is taken to avoid the ones which need dividing and staking, most kinds need no more work than shrubs.
The lifting and division of perennial flowers to keep the plants vigorous is often advised. It involves lifting, dividing and re-planting every three or four years. However, this work is not at all necessary for many species, and some positively dislike being shifted. The ons that need it are those which have a bald spot in the middle of the clump and they tend to wander. A decision can be made not to grow these plants, or to reduce them to a minimum.
Because the stems of perennial flowers are not woody, some kinds tend to be easily blown over by wind, and need to be staked. Many others, however, do not need staking – choose these. Heavy feeding with manures, while encouraging bigger displays, also contributes to the problem of floppy stems, on plants such as the Peruvian lily shown.
When perennial flowers die back in autumn, many books advise the removal of the dead flower stalks. However, these are best left in place until early spring, because most kinds are ornamental through the winter. They also provide over-wintering shelter for many beneficial animals.
When they are cut down in spring, it is a good idea to remove the stems to only half their height. The remainder is often quite stiff and will provide a measure of support for the new shoots. The top half of the dead shoots can be removed by clipping with a hedge-clippers.
Also when left until spring, the old shoots of many perennials have rotted at soil level and come away at the slightest tug, which is much easier that cutting them.
The debris can be removed to a compost heap, or simply chopped up and left to rot down around the plants. Removing only part of the stems by clipping reduces the amount of effort involved and makes it possible to tidy up a large area of perennial flowers very quickly. A strimmer can be used fro this job too.
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