Nacre bush, Kolkwitzia, Kolkwitzia amabilis – care and cutting

So that the phenomenal charisma of the mother-of-pearl bush comes into its own, cultivation as a solitary in a bed or in a tub should be considered first and foremost. In addition, the Kolkwitzia is suitable as a flowering hedge, in which case a little patience is required, because with an increase of 20 cm to 30 cm per year it takes some time before it serves as a privacy screen. Few factors need to be taken into account as part of care:

• Thrives in normal garden soil.
• Does not tolerate waterlogging.
• Sunny to partially shaded, sheltered location.
• The flowers are less abundant in the shade.
• Water young shrubs and container plants regularly.
• Later on, common rainfall is sufficient in the bed.
• Adult Kolkwitzia also tolerate longer dry periods.
• Now and then work in compost in particularly nutrient-poor soil.
• Container plants receive diluted liquid fertilizer every 4 weeks.

After flowering, the ovate, blunt-tipped, emerald-green leaves remain on the shrub all summer. In autumn, the Kolkwitzia amabilis brings color to the garden again thanks to the beautiful red-brown color of the leaves.

To cut

In addition to the lavish abundance of flowers, it is in particular the well-formed habit that underlines the charm of the mother-of-pearl bush. Cutting should therefore be limited to regular thinning:

• No cutting for the first three to four years.
• Cut off old branches close to the ground after flowering.
• Remove inward shoots.
• Eliminate crossing branches. If possible, leave one behind.
• Reduce recognizably weak new shoots by half.

The pruning of the mother-of-pearl bush is therefore carried out in such a way that an uninvolved observer does not even notice that the gardener was going to work with scissors. If, however, regular clearing is neglected every 2 to 3 years, the flowering bush loses its vitality. In principle, a tapering cut, i.e. placing it on the stick, is also possible with Kolkwitzia amabilis; In view of the slow growth, however, it will take years for a sizable shrub to develop again.

Hibernate the mother-of-pearl bush in the bucket

The flowering shrub from China is completely hardy outdoors. So that the Kolkwitzia can prepare accordingly for the dormant vegetation, it should only be ensured that it is no longer fertilized and cut or thinned from September onwards. When cultivating in the bucket, further measures must also be taken for wintering. Although the mother-of-pearl bush can cope with frosty temperatures without any problems, there is a risk that the root ball will freeze through in the bucket. It is therefore advisable to give him winter quarters.

• Check thoroughly for pests before putting them away.
• Store in a frost-free room at a maximum of 8 ° to 10 ° Celsius.
• Suitable rooms are garages, stairwells and greenhouses.
• A heated winter garden may be too warm.
• Place as airy as possible to prevent mold growth.
• Water only a little and do not fertilize.
• Pour only with water at room temperature.
• Ventilate the room well on sunny, frost-free days.
• Pay close attention to plant hygiene.
• Regularly clean the mother-of-pearl bush, remove weeds.

Depending on the temperature during winter, the Kolkwitzia sprouts early. There is nothing against taking it outside as early as April so that it can be hardened. In this case, however, you should receive protection against late frosts. Incidentally, the strong spring sun is also dangerous for the first flowers and leaves, so it protects a little shade from sunburn.

If there is no room for winter quarters available, the experienced gardener takes the following measures to ensure safe wintering in the bucket:

• Place the planter on a block of wood or styrofoam.
• Place on a house wall on the south side.
• Wrap the bucket with bubble wrap or bast mats.
• Cover the root ball from above with straw and brushwood.
• Give a small dose of water on frost-free days.
• Do not fertilize during the dormancy period.
• Protect the early shoots from frost with jute sacks.
• Do not place in the sun in the first weeks of spring.

If propagation with cuttings is planned, these are not cut before February.

Repot

Although the mother-of-pearl bush is one of the slow-growing subshrubs, it is necessary to repot it in a new planter after two to three years. A sure sign that the time is ripe for it are roots growing out of the water drainage hole or pushing upwards.

The new bucket should not be more than 10 cm larger in diameter than the previous one and it should definitely have a drainage hole for excess irrigation water. A drainage system made of pebbles, coarse sand or chopped pottery shards is created over it.

Conventional potting soil is suitable as a substrate. After the Kolkwitzia has been potted out of its previous planter, the experienced hobby gardener takes the opportunity to take a close look at the root ball. Dried or rotten pieces of root are cut off with a sharp knife and the cut wounds are closed with charcoal ash. Then a layer of potting soil is poured over the drainage and the mother-of-pearl bush is placed in the middle. The fresh substrate envelops the root ball up to a few centimeters below the edge of the bucket. In this way, the knowledgeable gardener ensures that nothing spills over when watering.

Since every repotting means stress for the Kolkwitzia amabilis, this measure is carried out in early spring, shortly before budding and not during the growth phase.

Diseases and pests

The mother-of-pearl bush is resistant to diseases and pests. If there are problems anyway, they are mostly due to neglect of care or non-parasitic causes:

Late frosts
Since the bell-shaped flowers of the Kolkwitzia already appear in May, they are at risk from sudden late frosts. The weather report should be followed closely in the period up to mid-May, because regional frosts are announced there. Garden lovers who want to protect the magical flower growth on their mother-of-pearl bush have jute sacks, garden fleece or bubble wrap ready to hand for this case. With just a few simple steps, the protective cover is put on and the blossoms are saved for this year.

Weather damage
Although it happens less and less in the context of global warming, it can still happen that the ice saints report back with a hailstorm by mid-May. Leaves, buds and flowers of the mother-of-pearl bush that have been damaged by hailstones should be removed immediately because they are susceptible to attack by fungi or pests.

De-icing salts
One of the many positive attributes of Kolkwitzia is its robust drought resistance. Should the leaves nevertheless curl up over the course of the summer, discolor and fall off, it is likely that they have been damaged by de-icing salts that have seeped into the ground. In the first step, the mother-of-pearl bush should be watered thoroughly, with the garden hose running for at least 1 hour. If the damage persists, a complete soil change is carried out, the plant is strengthened through regular fertilization and watered more frequently without waterlogging. As a preventive measure, you shouldn’t use de-icing salts around plants, but rather environmentally friendly grit, such as sand or charcoal ash.

Multiply

With hardy shrubs such as the Kolkwitzia, three methods are available for quick and efficient propagation:

Cuttings propagation

In contrast to a cutting, the cuttings have no leaves:

• Cut off annual, woody shoots on a frost-free day in February.
• Each 15 cm to 20 cm log has several leaf nodes.
• Cut the shoot tips of the cuttings straight.
• If the top leaf node is missing, this promotes rooting in the lower part.
• Cut the lower part at an angle to avoid confusion.
• Cuttings planted the wrong way round will not take root.
• Put 2/3 in pots with potting soil in a cool place.
• Keep the cuttings and substrate slightly moist while rooting.

Until a sufficiently strong root system has formed on the cuttings, it must not be too bright or near a sunny window, because otherwise there is a risk that the young shoots will spoil. By the way, gardening enthusiasts also practice the propagation of cuttings directly in the bed if there is not enough space in the house or in the greenhouse. In this case, 2/3 of the cuttings are stuck in a sheltered place in the garden directly into the non-frozen earth and lightly poured on frost-free days.

Cuttings

Those who prefer to propagate during the summer choose the cuttings method. On a mild day in June without blazing sunshine, a 15 cm to 20 cm long half woody shoot tip cuttings are cut. Completely green cuttings are far too soft and immature for this purpose to take root on their own.

• Completely defoliate the lower part of the cutting.
• Also remove all flowers.
• The top must have multiple leaf nodes.
• Leaf nodes can be recognized by thickenings under the bark.
• Fill a pot with potting soil.
• Pre-drill the insertion hole for the cutting.
• Plant half of the cutting in the ground and moisten it.
• Place in a not too bright, warm place.
• Keep the cuttings and substrate slightly moist, but do not soak them.
• Willow water promotes rooting.
• An overlaid transparent bag supports a suitable microclimate.
• At the same time, insects are prevented from laying their eggs in the substrate.
• Air the bag regularly to prevent mold from forming.
• If the roots grow out of the water drainage hole, the process is complete.

The warmer the location during propagation, the faster the pot will take root. With a little luck, the young mother-of-pearl bush will be ready for planting in the bed after three to four weeks.

Sinker

Thanks to its curved branches, Kolkwitzia amabilis is ideally suited for propagation by subsidence. The mother plant should not be too young, but strong and healthy:

• Select a flexible branch from the lower part of the bush.
• Pull this down to the ground and mark the spot.
• Loosen the soil there and use the spade to create a 10 cm deep groove.
• Defoliate the branch area between the gutter and the mother plant.
• Slightly score two or three places with a razor blade.
• Cover the sinker with earth and possibly weight it down with stones.
• Alternatively, prevent the shoot from jumping up with tent pegs.
• The tip of the shoot still has to look out of the earth.

When the sinker begins to grow, this is the signal that enough roots have formed. Separate the branch from the mother plant and dig up carefully so that the roots, which are still tender, are not damaged.

Conclusion
The mother-of-pearl bush keeps what its name promises. With its countless pale pink flower bells and its picturesque habit, it adorns the garden as a solitary or in a group as a flowering hedge. The frugal Kolkwitzia does not make any significant demands on the location and maintenance, so that it also thrives in less light-flooded corners. Diseases and pests cannot harm the flowering shrub as long as its roots are not permanently in water. In summer, the deciduous Kolkwitzia amabilis can even tolerate a long dry spell in the bed. In autumn, the mother-of-pearl bush once again attracts everyone’s attention with its deep red foliage before it falls into hibernation.