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Japanese spirea shrub: pruning and propagation of summer spirea. When is the right time to do this?

Japanese spirea shrub, still known as summer spirea, is an undemanding woody plant. With good care, the semi-shrub thanks you with a magnificent flowering, which pleases the eyes from early summer to autumn. In summer, in addition to fertilizing and watering, pruning and propagation are part of the program.

Japanese spirea shrub: the most important things about care in the summer summarized

Summersedge in the garden useful tips for care

The summer spirea is a small shrub from Asia (where it is native to South Korea and Japan) with a loose and slightly bushy habit. The ornamental shrub grows as tall as it is wide – about 120 to a maximum of 150 cm and gains 30 cm a year.

Japanese spirea: poisonous or non-toxic?

The Japanese spurge is not poisonous to humans and pets and is therefore suitable for planting in flower beds in the family garden. It also cuts a good figure as a hedge plant and is popular with amateur gardeners because of its dense growth.

By the way, the shrub spar is bee-friendly . However, its usefulness to pollinating insects can vary greatly from variety to variety.


A location in full sun proves to be optimal. The summer lime can also thrive in light shade, but the flower formation decreases. Otherwise, the shrub is considered undemanding and can easily withstand wind, snow and rain. In its native lands, it is found in mountainous areas. However, plant hardiness can vary from cultivar to cultivar, so it’s best to check with a garden center or local nursery.

Soil requirements

As for soil conditions, a moderately moist soil with pH in the acidic range and low lime content proves optimal. A layer of sand improves permeability, and regular supply of humus provides sufficient nutrients.

Japanese spirea shrub as a screen in the garden

Japanese spirea shrub: Care

The summer spirea is an uncomplicated plant. In the first years the shrub needs regular watering, from then on you can water only when necessary, for example, during prolonged heat. At the start of the garden season, you can provide the plant with slow-release fertilizer to encourage sprouting.

Flowering time

Its white to light pink flowers appear in umbels up to 20 inches tall around the beginning of July. The flowering period lasts until August, but can be extended until early September. The flowers give off a sweet aroma.

Planting in the garden and in containers

You can plant the pre-cultivated young plants, which are offered in garden centers, in tubs from spring to autumn. An important condition for this is that the permafrost is over and the temperatures in the ground at night do not fall below 0 ° Celsius.  If planting in the summer and prolonged heat, you should water the ornamental shrub abundantly. You can additionally mulch the young plants , so that the water does not evaporate too quickly. Planting in the garden should be done before or immediately after flowering. The optimal time is early autumn, before the permafrost sets in.

Use in the garden

As a soloist, the summer spar is mainly arranged in tubs on the terrace. In groups it becomes a real eye-catcher in the flowering hedge. It is also suitable for planting on slopes, as an accent around the front entrance or as part of a wildlife hedge.

Pruning summer spruce: Common mistakes to avoid

Properly prune in summer extend flowering time

Spireas that bloom in the spring need maintenance pruning in the summer. However, this should be done every two years rather than annually.

In contrast, the Japanese spirea shrub is cut back vigorously once in the spring. Since it blooms on this year’s wood, the old shoots are shortened to 15 cm in February. This encourages new sprouting and ensures abundant flowering in the summer.

Summer pruning, however, differs from vigorous pruning in the spring. Its aim is to prolong the flowering period. That is why withered flowers are cut off. Also, diseased or inward growing shoots are removed. If necessary, you can also thin out the shrub a little, so that all the shoots get enough sunlight.

Propagating the summer spirea in summer

Propagate summer spirea in the garden by cuttings

By the way, the Japanese spirea shrub can be propagated in the summer, at the end of the flowering season. In this country, propagation is usually done by cuttings, but in the USA, the plant can self-seed and multiply rapidly within a few years. Conservationists there repeatedly report that the invasive plant has spread there, even in nature reserves.

The summer pepper is an Asian shrub that is native to Korea, Japan and China. But even in the home garden, the undemanding woody plant can thrive without any problems and requires little care. Especially when pruning, you should pay attention to a few things, because the Japanese spirea shrub blooms on this year’s wood.