Water Lilies - Pests and Diseases!!
Avoid using chemical sprays whenever possible!!
If you have a light infestation you can spray off with a hose
into the pond every day, and fish will eat them. Keep repeating this until it
is under control.
Ladybugs are
one of the best known beneficial insects for controlling aphids!
A fun and cost effective treatment, simply
release them in areas of pest activity and allow them to do the work.
It is great to involve the
kids too! It is a fun project
for them and teaches them about nature and respecting the balance!
The key to healthy water
lilies is to catch the problem early before it has a chance to get out of
control!!
Waterlilies are a hearty
aquatic plant, so pests and
disease don’t occur often.
Other environmentally safe insect control is Diatomaceous
Earth, a microscopic abrasive that kills aphids and other insects. It can be
dusted on the leaves or mixed with water and sprayed. ALWAYS use food grade
Diatomaceous Earth. Nonfood grade is an irritant to the lungs.
MIDGES - Leaf-mining midges
make wavy marks in
the lily pads. These very small larvae can be
handpicked,
the leaves can be removed, or the
water can be treated with Mosquito Dunks.
China Mark Moth - The tiny brown moth is the waterlily’s biggest pest. It is
nocturnal and lays eggs underneath the large floating leaves. After the eggs
hatch, the larva slices leaf pieces to make protective sandwiches. These larva
will burrow into any floating leaves or debris. Their cycle runs about 2 weeks,
so keep a close check for them throughout the growing season.
The mechanical control
method, better known as squishing, works well to control an initial outbreak —
fish just love the worms! Bacillus thuringiensis (Bt), a natural bacteria, can
be used as a spray. Once ingested by the larva, it kills it but won’t hurt
people, pets or fish. If there is a severe infestation, the best remedy is to
remove all affected foliage close to the crown of the plant and destroy it.
Diseases
Several years ago, many
varieties of hardy lilies were susceptible to crown rot, a fungis disease. The
leaves on affected plants would turn yellow and curl up, and buds would rot
below the surface. The plant would die soon since the rhizome had rotten away,
leaving a stinky mess. Treatment was to completely soak the tuber in a
fungicide. Since the disease is highly contagious, the best option was to completely
remove the plant and destroy it. However luckily, this incidence and other
fungal diseases has decreased as less susceptible hybrids have been developed.
In addition to these natural treatments, it is always best to keep the body of water moving with a pond aerator or pond fountains. This will reduce that growth of algae and keep pests at a minimum.