Purple loosestrife: location, cutting & use


I study landscape ecology and through my studies have discovered a love for plants. Plants are not only beautiful, but also have countless fascinating survival strategies. To bring a bit of nature into my home as well, I nurture my houseplants and herbs on every possible windowsill.

Favourite fruit: rhubarb and all kinds of berries
Favourite vegetables: onions and garlic

Purple loosestrife makes any pond bank an eye-catcher. In fact, unlike many other plants, waterlogging does not bother him at all. But the adaptable purple loosestrife also feels at home in other places in the garden.

Purple loosestrife flower
Unlike many other plants, purple loosestrife is not bothered by waterlogging [Photo: Irina Papoyan/ Shutterstock.com]

Even in shallow water, but also in fresh garden soil, common loosestrife (Lythrum salicaria) thrives. The decorative flowers attract insects and, like the roots, can supposedly provide relief from various ailments. Learn here how to care for this special plant in your own garden.

Purple loosestrife: flowering period, properties and origin

Common loosestrife (Lythrum salicaria) is a popular ornamental plant that was also used in the past for medicinal purposes. The loosestrife genus (Lythrum) of the loosestrife family (Lythraceae) includes about 35 species. Common loosestrife is a perennial, herbaceous member of the genus and becomes woody over time. The perennial can reach a height of up to two metres. In its natural habitat areas in Europe and Asia, it is usually found in damp places. Parts of its shoots can even grow in the water. The lanceolate loosestrife leaves are arranged in threes in a whorl. From June to September, the purple loosestrife shows its purple colourfulness in the flowering season. The flowers sit in racemose or spike-like flowerheads on the shoots. Another species known to us for the garden is the rod loosestrife (Lythrum virgatum). Its flowers look very similar to those of common loosestrife. However, they sit at the end of the bare shoots up to one metre high.

Bee visiting the purple loosestrife
Insects also visit purple loosestrife regularly, including bees and bumblebees [Photo: delyrie/ Shutterstock.com]

Is purple loosestrife bee friendly? Yes, loosestrife is visited by bees, but also hoverflies, bumblebees and butterflies, and provides abundant nectar.

The most beautiful species and varieties

From the common loosestrife exist many varieties of different colours and sizes. Another species of purple loosestrife, switchgrass, is also known as an ornamental plant.

Common loosestrife (Lythrum salicaria)

  • Lythrum salicaria ‘Robert’: At 60 – 80 cm tall, this loosestrife variety remains rather small and compact.
  • Lythrum salicaria ‘Blush’: This variety also does not grow tall, at about 70 cm, and captivates with its flowers in a light pink.
Light pink flowers of the purple loosestrife blush
Some varieties, such as purple loosestrife ‘Blush’, flower in a light pink [Photo: Josie Elias/ Sutterstock.com]
  • Lythrum salicaria ‘Robin’: This variety blooms in purple-pink and grows compactly to a height of 80 cm.
  • Lythrum salicaria ‘Fire candle’: This loosestrife can grow as tall as 1.20 m and blooms in pink.

Rod loosestrife (Lythrum virgatum)

  • Lythrum virgatum ‘Dropmore Purple’: Purple loosestrife ‘Dropmore Purple’ forms purple, stately flowers and grows to about 80 cm tall.
  • Lythrum virgatum ‘Swirl’: The ‘Swirl’ variety is impressive with its pink flowers and a loose flowerhead. It grows to around 70 cm tall.
Flower of the purple looosestrife
Purple loosestrife has branched inflorescences [Photo: Vankich1/ Shutterstock.com]

Planting loosestrife: location and sowing

As long as the soil is sufficiently moist, loosestrife can be in a location in the sun. If you have a garden pond, the best place to plant loosestrife is on the shore of the pond. There it can grow even in the shallow water zone up to 10 cm deep in the water. However, the hardy plant also tolerates garden soils with less moisture, but then he should be in partial shade. However, in the shade, the flowering also turns out more sparse. To keep the soil moist longer, you can plant loosestrife in a pot in the garden soil. If the container has only a few drainage holes, less water can run off and the perennial is easier to keep moist. It is best to fill the pot with a substrate that holds water well, such as our Plantura Organic All Purpose Compost. It is made of natural raw materials and the nutrient supply provides the purple loosestrife with all the essential nutrients after planting. From spring to fall, you can plant loosestrife in small troops of no more than ten specimens – this is a great way to show off the perennial. Keep a distance of about 50 cm from other plants.

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Tip: Due to its water purifying effect, purple loosestrife is also often used in the cleaning zone of swimming ponds.

Blood loosestrife in the tub: It is also possible to keep the blood loosestrife in the tub. This should be sufficiently large so that the root ball has enough space. If you place the pot on a saucer filled with water, the purple loosestrife will be able to take care of itself and you will always see immediately when the water supply is running low.

Garden pond with purple loosestrife
Purple loosestrife feels most at home near bodies of water [Photo: Alexander Denisenko/ Shutterstock.com]

Caring for purple loosestrife: cutting and co.

The robust purple loosestrife is very uncomplicated in care. Nutrients should be replenished from time to time and the soil should always be slightly moist.

Always water so much that the soil is moistened or even wet. After all, loosestrife does not like dryness at all. If it stands by the pond, then hardly need watering. For potted plants should always be water in the saucer.

Pink flowers of the purple loosestrife
To ensure that purple loosestrife grows well, it should be watered regularly [Photo: Beekeepx/ Shutterstock.com]

To ensure a good supply of nutrients, purple loosestrife should be supplied with a slow-release fertiliser once in spring. A fertiliser with a high organic content, such as our Plantura All Purpose Plant Food, is ideal for this purpose. It supplies the plant for three months and only needs to be applied once for purple loosestrife. For the most part, it consists of organic ingredients and only needs to be lightly worked into the soil. Alternatively, if you have a compost, you can add two quarts of it to the soil when planting the loosestrife.

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In order for it to sprout beautifully again, you should cut the purple loosestrife. Pruning is possible both in autumn and spring.
Pruning after flowering in the fall mainly prevents self-seeding and uncontrolled spread of purple loosestrife. To do this, cut the shoots at the base just above the ground. The inflorescences are thus removed and fruit and seed formation is no longer possible.
If you refrain from pruning in the fall, you can still enjoy the beautiful discolouration of loosestrife leaves. In this case, the purple loosestrife should be cut back the following spring so that it can sprout vigorously again.

Is purple loosestrife hardy?

Purple loosestrife is hardy and can withstand temperatures as low as – 40 °C. Potted plants should be wrapped with fleece in cold winters, so that the substrate does not freeze through and the pot is not blown.

Propagate purple loosestrife

There are two ways to propagate purple loosestrife. The plant produces many seeds and is itself very prolific. If not cut back after flowering, there will probably soon be a few more specimens in the area. About seeds loosestrife is not propagated by variety, but you can collect the seeds and spread them yourself in the desired place. Sowing takes place in the spring and the seeds should be kept at a temperature of about 15 °C.

Purple loosestrife in snow
Purple loosestrife is hardy [Photo: Jarkko Jokelainen/ Shutterstock.com]

Cuttings can also be cut for single-variety propagation. To do this, in the spring cut off a young shoot, the parts of which can be divided among several pots. Alternatively, several cuttings can be separated from the tips of the shoots. Put them up to the leaves in pots with growing soil and keep them warm and moist. Special growing media such as our Plantura Organic Herb & Seeding Compost contain fewer nutrients so that the roots of the small plants develop magnificently. Our soil is peat-free and approved for organic farming. When new leaves form, the cuttings have formed roots and can be planted first in more nutrient-rich soil and then in the bed.

In addition, in the spring, loosestrife can be propagated by dividing the root ball. To do this, the plant must first be dug up.

Purple loosestrife tea
A purple loosestrife tea is said to help with gastrointestinal problems [Photo: Bankiras/ Shutterstock.com]

Effects and usage

The purple loosestrife contains, among other things, tannins and essential oils, which also makes it interesting for medicine. Mainly used are the roots, dried and boiled up as loosestrife tea, and the flowers. The tannins have a diuretic and hemostatic effect. Purple loosestrife is also said to help with inflammation, diarrhea or infectious diseases. The native wild perennial also provides food for bees and other insects and can be used as a cut flower besides.

Is purple loosestrife poisonous?

Purple loosestrife is not poisonous to humans or animals. It can be planted in the garden without hesitation and is even said to have healing properties.

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