Swamp sword lily, Iris pseudacorus – care and propagation

Profile of the beautiful swamp sword lily:

• The swamp sword lily Iris pseudocarus belongs to the Iris family
• Genus Iris, one of 11 Iris species in Central Europe (currently 390 Iris species are known worldwide)
• Perennial, perennial perennial that grows 1 to 2 m tall
• It is also known as the water lily or the yellow water lily because it colonizes the banks of water
• In the main flowering season in June, the iris develops expressive yellow flowers up to 10 cm in diameter
• This striking yellow flower is unique in the habitat, no species that bloom at the same time in the natural habitat show such bright yellow

The native Iris species is quite robust and is therefore ideal for planting in the shallow water areas of larger garden ponds. The narrow, sword-shaped leaves of up to 90 cm move in the wind like reeds, the bright yellow lily blossoms that appear from the end of May to mid-June also give the overgrown piece of pond edge a surprisingly exclusive look.

The swamp sword lily, also known as the “Queen of the Pond Bank” because of its imposing grace

• is easy to hold
• can cope with almost any soil, sun and partial shade
• develops a lot of green at impressive speed
• shows exceptionally noble yellow flowers from May / June
• hardly needs any maintenance, just enough water and fertilizer
• is unproblematic hardy – can withstand more than -35 degrees!
• knows no diseases and is not attacked by pests

= the swamp lily enriches every garden (and not only at the edge of the pond).

Possible locations

The swamp sword lily can decorate several locations in the garden:

Your “traditional place” is the swamp zone at the edge of the pond

• There it not only looks beautiful, but also works as a sewage plant:
• The rhizomes spread horizontally underground
• Many fine roots draw superfluous nutrients from the pond water
• Which the plant now serves as fertilizer
• Iris pseudacorus can be planted in a water depth of 0 to 30-40 cm
• It should grow best when it is occasionally hand-high in the water
• Full sun or very light penumbra are acceptable
• A little shade allows the flowers to last longer in the early summer heat
• If there is too much shade, however, the bloom will diminish
• The irises prefer medium hard water
• However, deviations in the direction of acidic or alkaline are largely tolerated

The elegant beauty is planted by landscapers on medium and large ponds. It is only a good choice for mini ponds if you are aware that “more lily than pond” will soon be seen in this area.

Far too little is known that the swamp sword lily also likes to decorate the garden away from the pond zone.

Even if the coarse leaves look succulent: Marsh sword lilies do not soak up to the tip of the leaf tubes with water, but their cavities are filled with air (for oxygen supply when the roots are stuck in air-poor mud). Like normal garden plants, they only absorb water through their roots, which is why they are just as unaffected by greater fluctuations in the water level up to the dried up pond bank as they are in the rest of the garden, when the soil there is normally well saturated with water.

Apart from that, the beautiful Iris hardly has any claims here either:

• The swamp sword lily does not really care whether the soil is acidic, neutral or calcareous
• Moist, slightly acidic soil is ideal
• Gladly clay-based, making it a plant for garden areas that are difficult to plant
• A lot of moisture is pleasant, but the iris can also tolerate prolonged dryness
• However, too long drought can affect flowering
• Above all, complete drying out in spring should be avoided as a matter of urgency
• In “dry locations”, I. pseudacorus remains smaller and does not spread as quickly
• By the way, swamp irises also grow “away from the pond zone” in prefabricated pond basins because they never get pond water

However, this applies to all locations

• The swamp sword lily is poisonous in all parts of the plant
• The poison is particularly concentrated in the rhizome
• Children and pets should therefore be kept away from the plants
• People at risk of allergies should put on gardening gloves before handling the plants
• Swamp irises can cause allergic skin irritation
• If the swamp lily spreads into the lawn or the like, caution is also advised with the rodent run
• Not all animals know what not to eat, and poisoning with marsh irises as a pasture weed is known

Soil preparation, sowing or planting

Swamp sword lily is quite hungry and thirsty, so it should be planted in well-nutrient-rich, moist soil. Usually not a problem at the edge of the pond, but normal garden soil often has to be prepared to feed a swamp lily:

• The soil should be rich in humus
• The soil must be able to hold moisture well
• Slightly loamy garden soils usually have just the right amount of permeability
• Well-cared for natural garden soils do not cause any problems either
• Sandy soils can be difficult because the water runs down past the shallow roots
• They should be enriched and compacted with some clay powder
• Otherwise, nutrient-poor soils cause more problems for the iris than over-fertilized ones
• Iris pseudacorus likes to pull excess nitrogen from over-fertilized soils
• In nutrient-poor sandy soils, mix in ripe compost before planting

Seeds of the Iris pseudacorus can be ordered over the Internet, but it is not for nothing that the information is often given with the seeds: “Experience is required when sowing and growing. Not suitable for beginners ”. If you want to give it a try, here’s what you should do:

• The cold germs should best be sown in late autumn or early winter
• As a dark germ, they have to be covered with soil more than a seed
• The nursery pots must remain outdoors or be placed in a cold frame
• Because in winter frost has to take effect, covering with snow should be an advantage
• The sowing must never dry out completely
• The seeds should then germinate in spring (from March to the end of April)

Occasionally, sowing in spring should also be successful if it is treated as follows: sow, keep normally warm and moist for 2-3 weeks, then put in the refrigerator for at least 4 weeks, then wait for germination in the open and plant out the vigorous young plants. This should not work for all varieties, a treatment with germ-accelerating gibberellic acid can help a little and possibly even replace the cold treatment in the refrigerator.

You can also purchase the water sword lily as a young plant and plant it out immediately. If you are patient and move the sword lily to one side with a place to spread, you can plant it as a specimen plant. If you want the beautiful iris to work quickly, it is better to plant it in a small group.

The best time for planting is autumn, the following applies at the edge of the pond and in the bed: Queens also need certain limits, because the beautiful marsh iris has a very strong urge to spread, which you can only control while planting:

• Iris pseudacorus forms a powerful rhizome as a permanent organ
• This rhizome creeps almost horizontally through the earth
• And constantly brings out new swamp iris
• Much to your delight when the swamp sword lily is to spread out
• Not so cheap if you want the iris to stay in place
• Or other, less competitive plants should also thrive in the shallow water zone
• That is why the swamp sword lily is usually planted in plant baskets and thus kept in check
• Often the swamp sword lilies are already sold in baskets, but you have to ask explicitly whether they are suitable as plant baskets
• You can also put the irises as a group in a large plant basket
• The spread can also be controlled a little via the exact location of the planting
• If the iris is not planted in the swamp area, but a little further in the damp meadow, it will grow less sprawling
• However, the starfish usually does not even get a meter high there

With the selection of the right location, the preparation of the soil at this location and the setting of the plant – as is almost always the case with native plants – the most important part of the maintenance is already done. Because with the locals you are dealing with plants that grow in the right location in the right soil without any problems because they correspond to their natural habitat. This often also decides whether a plant will continue to be well cared for, because at some point most gardeners lose the desire to look after a plant that is not satisfied at the location and that is constantly weakening (why some exotic plants that are ailing from the beginning are cared for with devotion for years is probably can only be explained with the purchase costs, which are usually many times higher for exotic species).

Ongoing care of the swamp iris

In pleasant surroundings, the yellow swamp sword lily behaves as it does in its natural habitat: it blooms profusely over the long term, even if it is not constantly divided and replanted.

To do this, it only needs enough moisture and from the beginning of budding (usually in March) until the near end of the growing season at the end of July / beginning of August, some good organic fertilizer (ripe compost, guano, plant manure). Do not fertilize on dry root balls (risk of burns), do not fertilize after the shoots have finished in mid-August (plants do not absorb any nutrients during the dormant period, they cannot mature properly and are more sensitive to frost with soft shoots); Otherwise the following applies to fertilizing: “Less is more”. The soil of the nitrogen-loving iris only needs to be improved a little if the clumps should later become blooming; then in spring fertilization is carried out from the start of budding until the yellow splendor is fully there again.

You don’t actually have to cut the yellow water lily, the wildflower usually blooms reliably if the dead shoots simply remain on the plant (and the iris can still draw a little food from them). If you want the garden pond to look neat, including the edge of the pond, you can also cut away all faded flowers, dead shoots and wilted leaves immediately; a primitive plant such as the swamp lily can easily take this away. You have the choice whether you remove the individual flower stalks (cut as far down as possible at the base) or cut back the entire eyrie including leaves, as is often recommended for “normal perennial pruning” (by natural gardeners, however, only in the first warm spring because the plant needs the foliage as winter protection).

Swamp sword lily: Obtaining and Propagating

The wild occurrences of the swamp sword lily are under nature protection; even if it still appears to be quite common in the wild, you should not take it to / from local waters. Firstly, it is forbidden, and secondly, you only need to imagine briefly what the wild occurrences look like if only some of the millions of home gardeners help themselves there.

You can get offspring of the original species and some cultivars of Iris pseudacorus in garden shops:

• Iris pseudacorus var. Bastardii grows to 1.2 m high and flowers in a light creamy yellow color in July / August
• Iris pseudacorus ‘Variegata’ becomes approx. 1.5 m high, drives pale buttery yellow fan leaves in early spring, which turn green in June and blooms in July / August yellow with brown accents
• Iris pseudacorus ‘Plena’ grows to 80 cm high and shows large, yellow, double flowers from May to July

The marsh sword lily can be propagated in several ways:

• The native wildflower initially spreads out to form considerable populations by itself
• This of course only if it is not prevented from doing so by a plant basket
• The swamp sword lily can be propagated vegetatively from this basket by dividing the rhizome
• A piece of rhizome is enough and many new irises can be created
• Divide in autumn / cut off piece of rhizome, plant immediately, the new swamp iris will come in spring
• The seeds of the marsh sword lily spread easily by self-sowing in the area
• The ripe seed pods can also be collected for seed production
• Sowing and the difficulties involved have already been described

Conclusion
Once again a wonderful, indigenous plant that many hobby gardeners have not yet discovered for themselves. With the (correct) planting of the swamp iris you will make gardening easier and you will help to preserve the diversity of the local nature, you will install an “automatic pond cleaning system” and make the domestic insects, which are currently badly troubled, happy – do you need more arguments?