Knotweed, climbing knotweed – care and propagation

The knotweed is a robust and undemanding plant that can thrive in almost any location. There are also no great demands on the quality of the garden soil, the plant is very adaptable. However, a warm location with sunshine over many hours is ideal, then the knotweed can develop rapidly under optimal conditions. A sheltered inner courtyard, house walls and garden walls are very suitable. However, if the location is too dark, the shoots will try to find the light and grow in the appropriate direction. In this case it can happen that the plant develops an undesired growth tendency and does not cover the intended area with greenery.

Due to the rapid growth, proliferation can also quickly occur, from which the neighboring plants will suffer. Therefore, the knotweed needs enough space, especially with regard to its future development. However, it can also be cultivated in a large flower pot or planter, in which it can then be variably moved if necessary if it bothers other plants or if it grows in the wrong direction.

• Sunny to semi-shady location, protected from heavy rain and wind
• Also thrives in the shade, but not as luxuriantly
• Tolerates all sufficiently moist soils, from alkaline to acidic
• Avoid constant drafts, which confuse the shoots
• Plan enough space, do not put too close to other plants
• Fertile and nutrient-rich soil, rich in humus, is ideal
• Growing in buckets possible
• Prefer humus and nutrient-rich plant substrate in the bucket
• Loosened soil ensures good oxygen supply to the roots
• If the soil is too loamy, lay a drainage against the moisture
• Use drainage made of crushed stone or coarse gravel below the root ball
• In the case of extremely strong root growth, pruning or repotting is necessary
• For planting, dig out a proportion of the soil and mix in some mature compost
• Ideal time for planting: spring to early summer
• Immediately after planting, water the plant extensively

watering and fertilizing

The knotweed can cope with all types of soil, but it must not be too dry and must be watered sufficiently if it is dry for a long time. Too little water is very harmful for the plant, if there are prolonged periods of drought due to the weather, these lead to dried-up leaves and severely inhibited growth of the flowers and leaves. It is best to collect the rain in a bin in the garden, as this water is not as hard and calcareous as conventional tap water. Regular fertilization is also appropriate to support and promote growth, especially if unsightly areas are to be covered quickly.

• Always keep the root ball reasonably moist, but never too wet
• Check the soil regularly by finger testing, especially during dry periods
• Water more often in the hot summer when there is little rainfall
• Use rainwater for watering
• Fertilize from spring to fall
• Organic vegetable fertilizer is ideal
• Normal fertilization, plant is relatively undemanding, about once a month
• Give a little more fertilizer during the flowering period
• Do not overdo fertilizing, otherwise it can have a negative effect

flowers, fruits and leaves

The small flowers of the plant are bright white and stand together in loose panicles, but there are also subspecies that have pale pink flowers. During the flowering period, these appear in abundance, so that the entire knotweed looks like a white or pink cloud. The flowers smell very pleasant and attract many insects, especially the bees welcome gardeners for pollination. The flowering period is species dependent and usually starts in early summer and can last well into autumn. The fruit of the knotweed is a small nutlet in a triangular shape, which is enclosed by the perianth and is not clearly visible. Due to the very dense growth of the shoots and leaves, birds appreciate this climbing plant as a breeding ground and nest here with their offspring.

• Flower spikes are about 16 – 18 cm long, with white or pink flowers
• Sweet scent, very intense as the plant grows
• Flowering period: July to October in white
• Medium green leaves, oval to heart-shaped, 5 – 9 cm long
• Growing foliage is red at first, then turns green
• In autumn the leaves turn light yellow to brown

Growth, climbing frame and pruning

If there is enough space to develop, the knotweed can be left alone and find its own way. In this case, you only have to cut back the shoots that go beyond the desired length. The deciduous creeper can grow extremely high and very wide. The climbing plant is particularly fast-growing and creates several meters per year under optimal growth conditions.

With increasing size, a supporting climbing aid is required, for example a stable trellis. In addition, a covering with robust wires that fix the position helps him. If you plant the knotweed on a dead tree, a fence or other surface that gives it enough support, it can develop independently without any problems. If the tangle of the shoots becomes too strong, the tangled areas should be thinned out. Even slightly older plants, in which the tangle of branches is already very intricate, are happy about a rejuvenating cut. The shoots should be cut back until just before they sprout, leaving the framework of the main branches standing.

• The climbing plant has a strong urge to spread
• Can grow 10-17 feet tall
• Annual growth of up to 5 meters
• Tolerates any type of pruning, even to the base
• Best pruned in spring
• Shoots can be cut back as desired
• Radical pruning to prevent tangled and impenetrable branches
• Radical cut about every 5-6 years
• Annual pruning will prevent bald spots on the bottom
• Encourage flowering by pruning
• If there is little space and proximity to the neighboring property, regular sharp pruning of the corresponding shoots

propagation

The knotweed is very easy to propagate and replant. With each propagation, you should choose the new location carefully to avoid nuisance from the rampant growth.

• Sowing possible in spring
• Propagation in summer by cuttings from herbaceous material
• In winter by sticks that are cut off
• Propagate in warm and sheltered locations in winter, transfer outside in spring

hibernate

The knotweed is a fairly frost-hardy plant that can easily survive the winter in the local latitudes. If a sheltered location has been selected, prolonged snowfalls and permanent sub-zero temperatures cannot harm it. Nevertheless, protection from the cold against excessive frost is highly recommended, especially if the location is clearly exposed and exposed to the weather conditions. If the temperatures are very low for an extremely long time, the climber will contract, but the next spring it will sprout again and profusely.

• Hardy plant that survives frosty temperatures unscathed
• Before planting, choose a sheltered spot for problem-free overwintering
• Courtyards, house walls sheltered from the wind, walls and fences are ideal
• To be on the safe side, attach antifreeze (twigs, tarps, etc.)
• Do not fertilize in winter

diseases and pests

The knotweed is relatively robust against diseases and pests, under ideal living conditions and with the right care, it only very rarely gets sick or is attacked by pests. As with all plants living outside, it can also be infested with aphids . If it is not watered enough, the leaves die off very quickly and become unsightly and dry.

aphids

• Wash off with mild soapy water, do not let it drip onto the floor
• Wipe off large infestations with your fingers

Conclusion
The knotweed is an attractive climbing plant that beguiles with lush green leaves and sweet-smelling flowers. It is a relatively uncomplicated plant that does not require any special care. The lush growth can ideally be used to cover up ugly spots and spots, but the overgrowth can also cause problems with other plants and with the neighbors. For this reason, sprawling shoots should be pruned in good time. The knotweed is hardy and can live for several years under optimal growth conditions.