Disease appearance in palms

In this manual we explain how to combat palm diseases and how to keep your leaves a nice dark green.

We also explain how you can best care for your hardy palms during the winter period.

Caring for palm trees during the winter period

In our Dutch climate, palms do not grow natively. However, it is becoming increasingly easier to keep palms in the Netherlands.

We have winter-hardy palm species in our range, such as the Trachycarpus Fortunei or the Trachycarpus Wagnerianus.

These palms can tolerate low temperatures of up to -18. Did you know that palms are emotional plants?

This means that if the perceived temperature is -18 (e.g. -12 with a strong wind), the palm is already at its maximum!

Palms also do not like prolonged frost of minus 10-13 degrees. That is why we recommend that you also wrap the palms in a frost protection cover during longer cold periods (at least a week).

Hardy palm trees

It is also important to know whether the palm comes from Spain or is extra hardened. A hardened palm is more expensive than a palm that comes fresh from Spain, but is stronger to survive the winter. This is because it is the same species, but the palm that is grown in Spain is of course not used to cold Dutch winters. A hardened palm or a palm from Northern France is of course much stronger than a palm that has always been nice and warm.

In the open ground

It is also important to know that a palm is much stronger in the open ground than in a pot, for example. This is because the roots can freeze in a pot, but not in the open ground, because at a meter below ground the temperature never drops below zero degrees. That is why it is important to take this into account with palms in a pot.

How can you recognize winter damage to palm trees?

Palm trees that have suffered from excessively cold temperatures may show 'frost': dark green spots on the leaves or completely dried out leaves.

These are signs of leaf damage.

If the leaves are frozen, these spots will turn brown/yellow in color.

In most cases the palm can still be saved. You can remove the ugly leaves and the palm will get a new crown of leaves in the spring.

Spear rot

If you can pull the spear out, this indicates spear rot, and as a last resort you can put the palm under a roof, so that no more water can get into the heart of the palm. In some cases a new leaf will grow, and the palm will come back to life. If after a month no leaf has grown, as a last resort you can saw the trunk down to the hard part, so that the rotten part is removed.

Dead or alive?

Check if the palm is still alive? You can do this by pulling the spear (also called the core) of the palm. If you can pull the leaves out of the core, then the palm has unfortunately died. If they are still firmly attached, then the palm will survive in almost all cases.

Help, the leaves of my palm tree are turning yellow

We often see that palms that are first a nice dark green, later turn yellow. In most cases this can be remedied by doing the bottom things:

- Does it only happen with the lower leaves? Then it is not a problem, and you can cut these leaves off. That is normal, that is its growth habit.

- It is also possible that the palm does this just after the winter period. You can cut off the yellow leaves and feed it well with Teeninga Palm Bacterial Food Granules , so that it will recover its growth.

- It can be caused by too little water in a warm period, but it can also have happened in the winter period (the palm also needs water in the winter). Unfortunately, this can no longer be remedied. In most cases, the ugly leaves need to be removed. No worries, they will simply grow back from the core of the palm.

- It could also be a nutritional deficiency. We therefore always recommend using Teeninga Palmen Bacterial Nutrition Granules , so that your palm keeps beautiful dark green leaves.

- It could also be caused by frost damage, in which case we recommend that you remove the unsightly leaves.

In almost all cases it is best to remove the ugly leaves after the winter period and also use Teeninga Palm Bacterial Nutrition Granules so that your palm will grow beautiful dark green leaves again.

Brown also known as rust spots on your leaves

Your palm tree leaves are showing rust colored spots also known as copper colored leaves.

This is because the palm has probably had too much sun.

We recommend that you allow the palms to acclimatise evenly to the number of hours of sunshine.

Unfortunately, these leaves will not recover and need to be cut off.

Black or brown spots on your palm leaf

These spots indicate root damage.

This could be because the soil is too wet or too dry.

This usually happens in the winter months because it is actually too wet for the palm tree.

We recommend that you check carefully whether the soil is too moist or too dry and, if necessary, provide the palm with the correct needs.

For palm trees planted in the open ground, we recommend that you place a layer of coarse gravel under the roots so that excess water can drain away.

Dried leaves

When the leaves dry out without this being due to winter damage, sun damage or a pest, the cause must be sought in the roots.

We therefore recommend that you check the roots carefully.

There are several possible causes:

The root ball is too moist, there is a poor clay root ball, or a fungal infection (fusarium).

The carrots should look fresh in color, and should not feel mushy or smelly.

If this is not the case, the ugly and smelly parts must be removed.

What is the best thing to do? Place the palm in dry potting soil and limit the number of waterings.

If the roots are black, this indicates a fungal infection. This only happens in North Africa, and the palm should be destroyed.

Various plagues

There are all sorts of pests for palm trees, ranging from aphids to destructive insects. Read all about them here.

Aphid / Scale insect

Aphids and scale insects are often seen on palm trees and are easy to treat with a mixture of methylated spirits, green soap and water: 2 spoons of green soap and 3 caps of methylated spirits.

There are also many remedies available at hardware stores, but so far, grandma's remedy works best.

Spray everything repeatedly, including the pot and potting soil, so that no survivors are left.

Spider mite

These small red (sometimes white) spiders are very small and difficult to see with the naked eye.

But you can see it on the palm. Usually the palm shows silvery speckles on the upper side of the leaf.

Eventually the leaf will become ugly and die. Also small woolly balls will develop on the underside of the leaf.

In most cases this is caused by a location that is too dry and often occurs with indoor palms and humidity that is too low.

This can be removed by spraying the plant and putting a clove of garlic in the potting soil. The infected leaves should be removed.

Palm moth

This moth, also called Paysandisia Archon, was introduced into Europe by the import of South American palms.

It is native to Argentina.

In Europe it has so far only been reported in southern France.

Fortunately, it is not a major traveler, but palms that are near the infected palm are certainly a potential host.

The eggs, the size of a grain of rice, are laid in the bases of leaves by the moth, which can grow to about 11 cm in size.

Most often the victims are the Trachycarpus species or the Chamaerops.

Fortunately, there is no evidence yet that the palm moth has entered the Netherlands.

If your palm tree is affected by the palm moth, the only solution is to burn the tree.

Red palm beetle

The red palm weevil is the worst pest that can happen to a palm lover. It eats the entire palm tree from the inside with its larvae.

The red palm weevil lays about 300 eggs per day and can completely destroy a mature palm tree within 3 months.

This beetle has caused a lot of damage in the Middle East. It originates from India and has fortunately not yet been spotted in the Netherlands.

The only method is to destroy the palm to prevent further spread.

Caterpillar

In most cases, palm trees do not suffer from caterpillar damage very often.

This is because the leaf is tough, which the caterpillar cannot actually bite through.

It is only sometimes the case with young seedlings.

It can be easily remedied by removing the caterpillars by hand.

The fern weevil

This small fly looks a lot like the fruit fly, but is slightly smaller.

He lays his eggs in moist soil.

The flies are not so much harmful to the plant. They reproduce very quickly, which means that the living room is soon swarming with flies.

However, the larvae can be harmful to weaker plants. To combat them, you can use a vacuum cleaner by holding it above the pot and tapping it against the pot so that they are sucked up. Use this to catch as many as possible. If this is repeated daily for a week, the problem will be largely solved. The potting soil can also be watered with an infusion of tobacco. This is harmless to the plant, but kills the larvae. Admire from BayerGarden is very effective as a chemical control.

Closure

Of course there are more pests that your palms can get. We have listed the most common ones for you in this article.

If you have any further questions, please contact us.