Mourning flies: how to get rid of them

Do very small and especially dull flies sometimes fly around your plant pots? They fly around the leaves, multiply around the roots and dust up as soon as you water them. The phenomenon called a mourning fly. For about 90% then!

Luckily there is something to do about those nasty creatures. Although fighting mourning flies can still be quite a job. Mourning flies are small, but very persistent.

How do you recognize mourning flies?

Funeral flies are very similar to fruit flies. They are both small, do not fly very fast and are very black. Although there is an important difference! Where fruit flies graze around fruit, vegetables and other organic material, mourning flies stay away from them.

Where mourning flies do offend are plants! Mourning flies are attracted by the moist soil and rotting roots. Does your plant suffer from root rot? Then it may be that mourning flies point out this problem very quickly.

Remarkable: despite the fact that an ecosystem regulates itself completely, fungi in addition to fungi in an ecosystem can also develop mourning flies. The mourning flies in an ecosystem are caused by the amount of moisture in the closed environment.

How can you fight mourning flies?

Step 1: Take a closer look at your plants

First of all, check all your plants. But then really all your plants! Do you detect mourning flies on more than one plant? Then separate the infected plants from the still clean plants as soon as possible. This will not only prevent the mourning flies from crossing easily. There is also less room to lay eggs. This in turn reduces the plague of mourning flies.

Always check new plants for fungi, diseases and pests. It may be that a new plant has taken those annoying mourning flies with it. By checking plants now and then, you’ll be on time in most cases. And because you discover the mourning flies quickly, control is still possible.

Step 2: Stop watering the plant

Avoid the watering can. And we don’t mean one week! No, keep this for at least 2 weeks. Especially at the end of summer it is no problem that a plant gets less water.

By stopping watering the soil will dry up. At such a moment there is no moisture in which larvae can lay their eggs! The water stop also reduces root rot.

Besides not giving water you can sprinkle sand on top of the potting soil. Most mourning flies can’t pass through the sand, and the larvae can’t escape either because of the density of the sand.

Step 3: Add wine to the soil

Do you still have an open bottle of wine in the house? Or would you like to have a drink? Then we recommend pouring the other half of the wine into trays. Seems a shame, but nothing could be further from the truth!

Pouring wine in trays makes the chance big that mourning flies will disappear. That saves costs for new plants!

Just like you, mourning flies love wine. As soon as they get a little too close to the wine they will drown one by one. It is best to cover the container with plastic and prick holes in it. This will reduce the chance of funeral flies escaping.

Step 4: Add nematodes between the roots

Do you still suffer from mourning flies? Then you are dealing with a persistent plague! In this case, it is best to buy nematodes and release them into the flowerpot.

These worms eat the larvae of mourning flies. Because of this, not only the mourning flies, but also the nematodes will disappear by themselves.

As soon as all larvae have run out, the nematodes no longer have nutrition. Which in time results in dead nematodes!

1. Are mourning flies preventable?

Yes! Just give less water. Mourning flies like moisture best, and enjoy root rot.

If you don’t water more than necessary, root rot will not occur. And the mourning flies probably won’t either.

It is also important to always repot with fresh potting soil. In a used bag of potting soil vermin can develop without you noticing. Especially when this bag is on a moist spot! The mourning flies will therefore not immediately stand out.

Probably the mourning flies are still hidden as eggs. You will probably only notice this when you have the plant in the room for a few days. With that ‘new’ potting soil.

2. Where to buy nematodes?

That’s a good question! They’re not at the supermarket, but in most cases they can be found in garden centers. Especially the larger garden centers! You can also find nematodes in the pet store.

No time to go to the store? You can also order nematodes online! We have had good experiences with Ecostyle.