The hardy varieties of the water lily have a thicker leaf than the tropical
water lily. Because the leaves on the tropical water lily are thinner they
require delicate handling and are more likely to be damaged in storms, high
winds and in the colder months of fall and winter.
Tropical water lilies thrive best in shallow water ponds or on the sides of the
water garden where the water is thinner. Seedlings often will spurt up from the
shallow depths of the water and they will even seed in the containers near the
water lilies where other plants are growing. To keep your tropicals from rotting
out, be sure the you plant in temperatures that are seventy degrees or higher,
that you keep gravel from touching the stalks of the plants, and you only place
the tropical water lily in the water up to where the stalk to the plant starts.
When the winter months are approaching you, can cover the pond with a plastic
covering, similar to that of a greenhouse and prolong the life span of the
tropical water lily and to protect the water lily from the elements of the
colder weathers.
Crown rot is a disease that often affects the tropical water lily more often
than the hardy lily. You will find soft black spots and areas on the leaves and
the stems of the water lily. If you find a terrible smell coming from your water
lilies this could be the black rot settling in the roots and pulling back the
gravel you will see the black remains of the once white roots. Black rot is a
fungus and getting rid of the infected plant is going to be one of the best
remedies.
Leaf spots on tropical water lilies are another fungus that can infect the
entire water garden. The leaves turning brown, curling up and appearing very dry
are often the signs of leaf spots. All the damaged leaves should be removed from
plants, and if plants are more than half covered in bad leaf spots, removing the
plant from the water garden will help control this fungus.
Leaf miners are tiny critters that like the fragile water lilies. The little
insects will lay eggs in the leaves of the lilies and then when they hatch they
will eat all that they can from the leaves of your lilies leaving small trails
through the leaves that looks as if someone scribbled all over the leaves.
Infected plants should be removed from the water garden leaving lilies in the
pool that do not have any marks on their leaves.