Thousand leaf, Myriophyllum – profile + care information

The various species within the genus boast optical and physiological properties that distinguish the milfoil from other aquatic plants in the submerged plant zone. It is not only the filigree nature of the tendrils, which are densely covered with whorls of pinnate leaves, that catches the eye. In addition, the cosmopolitan aquatic plant is the only deep zone plant that is able to present its graceful flowers on the surface of the water. Some varieties also score with reddish stems or leaves with a hint of red. This play of colors is particularly appreciated by aquarists and cultivates milfoil as a decorative background plant. Last but not least, the entire Myriophyllum genus has useful attributes. In this way, the plant actively participates in maintaining clean water quality.

Maintenance in the garden pond

The Brazilian milfoil (Myriophyllum aquaticum), the spiky milfoil (Myriophyllum spicatum) and the whorleaved milfoil (Myriophyllum verticillatum L.) are popular among hobby gardeners in garden waters and wetlands. Since these species are native to our regions or have been wild for more than 100 years, they have a robust constitution and sufficient winter hardiness. The following care information covers all the important details.

location

The more sunlight the aquatic plant receives, the more luxuriant the growth and the denser the summer floral flora. The parrot feather feels just as well taken care of in slowly flowing water as it does in standing water over muddy ground. This results in a high degree of flexibility in terms of suitable site conditions. It depends on these aspects:

• Sunny to partially shaded location
• Gladly soft to medium-hard water
• Water depth from 40 to 100 cm
• Rich in nutrients, poor in algae
• Humous soil with a pH of 5.5 to 6.0

Under optimal conditions, the thousand-leaf plant thrives both submerged (under the water surface) and emersed (above the water). The more intense the sunlight, the more densely a green carpet of filigree pinnate leaves develops, which can rise up to 50 cm in height. While the Brazilian milfoil attaches great importance to the cleanest possible water quality, the eared milfoil proves to be tolerant of pollution. Likewise, the whorl-leaved thousand-leaf does not wilt so quickly even in a pond that is rich in turbidity.

Fertilize

One of the many tasks of parrot feathers is to help keep the water clean. Since it is primarily algae that destroy the dream of crystal clear pond water, Myriophyllum deprives the green dwarfs of their livelihood due to its nutrient consumption. The targeted application of fertilizer would therefore have counterproductive consequences. Do not fertilize thousand leaves according to a firmly cemented plan, but only when there are obvious signs of deficiency. However, poor growth, dull colors, brown or yellow leaf tips indicate a need for nutrients. If a shady location or water that is too hard can be excluded as a trigger, proceed as follows:

• Only fertilize the millennium when a lack of nutrients is evident
• Ideally, apply a special pond fertilizer and not a common plant fertilizer
• Liquid preparations are preferable to granules or tablets

Handle the dosage with a sure instinct, because re-fertilizing is much less complicated than revising an over-fertilization. Since the majority of Myriophyllum thrive submerged and emersed, please make sure that the preparation does not get on the parts of the plant above the water surface. Otherwise fatal burns on the magnificent leaflet whorls could result. As soon as the freshwater plant has recovered, stop using fertilizers.

To cut

Compared to other aquatic plants, the milfoil rarely tends to overgrow. Nevertheless, a Myriophyllum can achieve an impressive volume in the ideal location and with loving care. How good that the delicate plant is so easy to cut. How to do it right:

• Regularly clean out withered shoots
• Thoroughly thin out once or twice a season
• In autumn, cut back vigorously by at least half

Experienced hobby gardeners cut back a mighty parrot feather several times per season if they are aiming for bushy growth. Experience has shown that a shortened stem branches at least twice from the leaf axil below the cut.

Overwinter

If you cultivate native Myriophyllum species in our regions in the large pond, they are completely hardy. The spiked, Brazilian or whorleaved milfoil do not require any special precautions in order to survive the cold season in good health. Cut off withered tendrils in autumn, as they no longer make a useful contribution to the ecosystem and impair the visual appearance. By means of winter buds, the so-called turions, the plant independently takes care of the next year’s budding. These vegetative wintering organs sink to the ground, where they survive the cold season unscathed.

However, if the aquatic plant thrives in the limited volume of a patio pond or mini pond, it will move to a bright, frost-free winter quarters in late autumn. If the temperatures fluctuate between 5 and 10 degrees Celsius there, the plant falls into a restful dormancy and sprouts again in spring. To prevent rot, carefully remove all withered and withered parts of the plant before moving.

Care in the aquarium

In the protected ambience of the aquarium, the colorful tropical Myriophyllum species, such as the red thousand-leaf, provide us with a decorative background planting all year round. Furthermore, there is nothing to prevent the robust Brazilian thousand-leaf or its garden pond-suitable conspecifics from also settling in the water world of the living room, provided that it is a cold water aquarium. The following care information focuses on all the important differences to cultivation in garden water.

Acclimatize after purchase

Nurseries usually cultivate thousand-leaf species emersed, in pots with a moist substrate. This form of cultivation aims at the growth of thicker, stable stems, as they are quite desirable in the pond. For submerged cultivation in the aquarium, however, an acclimatization phase is recommended. This is how you do it:

• Pour a nutrient-rich substrate into a basin
• Use the freshly acquired freshwater plants
• Keep the water level at a low level of a few centimeters

In the following period, increase the water level by a few centimeters every day until the desired water depth is reached.

Fertilize in a balanced way

The exotic Myriophyllum species are demanding aquarium plants that require a balanced supply of nutrients in addition to a sunny location and soft water. While their robust conspecifics in the garden pond are only fertilized when there are deficiency symptoms, this maintenance measure is carried out regularly in the aquarium. It is important to maintain the balance between nitrate with 5-15 mg per liter to phosphate with 1-2 mg per liter (values ​​for the red thousand leaf). There are also important trace elements such as iron and minerals. If there is an imbalance here, the parrot feather clearly lags behind in growth, loses its splendid color and ultimately dies. Special aquarium fertilizers are available in specialist shops that contain all the important ingredients for a healthy aquatic plant.

Supply of carbon dioxide

As a stem plant, the milfoil takes up its food mainly through the leaves, with the roots mainly serving as anchoring in the ground. If there are few or no fish romping about in the water, while the location is only partially shaded, the addition of fertilizer with carbon dioxide should be added. The supply of CO2 is not essential for life, but it certainly has an accelerating effect on the growth and beauty of aquatic plants.
Suppliers of carbon dioxide are the fish with their breathing, various microorganisms and the air in the room. In the water of the aquarium, carbon dioxide is partially converted into carbonic acid and is immediately available for Myriophyllum. If this natural supply is exhausted, the aquatic plants use the lime, whereupon the pH value becomes unstable and the small ecosystem finally begins to falter. The controlled supply of CO2 provides a remedy. For orientation with regard to the dosage, a long-term test uses different colors to show the level of carbon dioxide in the water.

An overview of the thousand-leaf species

The following list of the most important Myriophyllum species for ponds and aquariums with an assessment of the maintenance level, may serve as a guide:

Brazilian milfoil (Myriophyllum aquaticum)

• At home in South America, overgrown in Germany
• Suitable for banks and deep zones
• Posture: medium

Ähriges Tausendblatt (Myriophyllum spicatum)

• Native to Africa, Asia and Europe
• Ideal for standing water
• Attitude: easy

Quirlblättriges milfoil (Myriopyhllum verticilliatum)

• Native to the northern hemisphere
• Favors flowing waters, tolerates water containing turbidity
• Attitude: easy

Red milfoil (Myriophyllum tuberculatum)

• Native to tropical Asia
• Thrives in slow-flowing and stagnant water
• Attitude: demanding

Small parrot leaf (Myriophyllum hippuroides)

• Located in North America
• Perfect as a background plant in the aquarium
• Attitude: easy

Japanese milfoil (Myriophyllum ussuriense)

• Native to Southeast Asia
• Suitable for garden water and aquarium alike
• Attitude: easy

Conclusion
The multi-faceted Myriophyllum genus gives pond owners and aquarists a wide range of decorative and useful thousand-leaf species. Thanks to its long tendrils, covered over and over with whorls of filigree pinnate leaves, the low-zone plant has established itself as one of the most popular background greening in bodies of water, wet biotopes and aquariums. The “Tausendblatt” has this status not least because it is frugal and undemanding. In the sunny to partially shaded location, in soft to medium-hard water, it thrives tirelessly and impressively sets itself in the limelight with a summer bloom. In the garden pond, fertilizer is only required if there are deficiency symptoms. The plant also only requires pruning if necessary. Hardy species sprout again even after a frosty stay under a closed ice cover. If you move the Myriophyllum in the mini pond or water garden to winter quarters with temperatures of 5-10 degrees Celsius in good time, they will turn your water landscape into a green refuge again next summer.