From spring to autumn all kinds of insects cavort on the leaves and flowers of the water lilies. Most of them are perfectly harmless. But some species are so voracious that they seriously endanger the life of these aquatic plants.
Water lilies also fall victim to pests
water lice
Lice love all parts of the water lily plant, but they prefer the underside of the floating leaves. Their sucking activity means that bright spots will soon appear. In addition, the leaves curl. The water lily aphids are dark green to black in color and about 1-2 mm long.
You should fight water lily lice, because their honeydew clogs the stomata of the leaves, which in turn promotes fungal diseases. Since any chemical control measure can significantly disturb the ecological balance in the pond, you should absolutely avoid it. Instead, we recommend:
- manual lice stripping
- Spray down with a water jet
- Sprinkle with horsetail broth
tips
Severely affected leaves should be cut off and discarded. If necessary, you must completely remove diseased specimens from the pond so that the infestation does not spread further.
Water lily leaf beetle and its larvae
The beetle itself hardly harms the water lilies, while its larvae know no bounds in their gluttony. It is they who eat the leaves bare. First the surface of the leaf is scraped off, later holes appear. Very rarely, flowers are also affected.
An infestation can be expected from May. The water lily leaf beetles then lay numerous eggs on the upper side of the leaves of the water lilies, from which the larvae hatch within a few days. Here are a few key data:
- Beetles are grey-brown
- about 6-8 mm long
- Eggs are yellow-brownish
- their diameter is about 2 mm
- Larvae are dark brown, yellowish underneath
Collect discovered beetles and larvae by hand, destroy the clutches. Heavily infested leaves should be completely removed and discarded.
More pests
There is also a risk of other pests eating the leaves and stems of the water lilies. For example, from the 2.5 cm long, initially green and later greyish caterpillars of the water lily borer (water butterfly). As early as March, pointed mud snails and mosquito larvae can cause damage.
Prevent and control
Since chemical pest control can cause considerable damage to other pond inhabitants, the focus should be on preventive measures and early detection. For example, robust native varieties are less sensitive than tropical species. Optimal care also makes water lilies more resistant. In addition, check your plants regularly for possible pests so that you can stop their spread at an early stage by taking suitable measures.