Plants are living creatures that will thrive if you take good care of them, but sometimes it just goes wrong.
In this overview we will help you diagnose, prevent and treat the most common plant diseases!
For all affected plants there's just one rule: separate them from your healthy plants to keep diseases from spreading.
1. MEALY BUGS (wolluis)
Small fuzzy white insects that look like cotton fluff.
Prevention : Try to weekly check your plants for bugs to prevent them from developing. Mealy bugs often appear when the air is very dry (both in summer and in winter when your heating is on) so regularly misting your plants to increase humidity will definitely help.
Very common on Palms, Cacti & Succulents.
Treatment : As soon as you spot a mealy bug, treat your plant immediately because they can spread quickly. A simple way is to remove adult bugs with cotton swabs (or an old tooth brush) soaked in alcohol or detergent. Make sure to rinse all the leaves with water afterwards (cover the soil with plastic while you're doing this). For larger infestations, it's best to use Chrysopa larvae that will eat the mealy bugs.
We recommend to use Chrysopa larvae:
2. SPIDER MITES (spint)
Super tiny spiders that leave very fine webbing on the leaves and stems of your plant. Leaves often look deformed, curled or change colour.
Prevention : Try to weekly check your plants for bugs to prevent them from developing. Spider mites also appear when the air is very dry (both in summer and in winter when your heating is on) so regularly misting your plants to increase humidity will definitely help.
Very common on Calathea & Alocasia.
Treatment : As soon as you spot spider mites, give your plant a good shower to rinse off all the bugs. Wipe down the leaves with a damp cloth and soap (cover the soil with plastic while you're doing this). It's also recommended to cut away the most affected leaves. For larger infestations, it's best to use predatory mites that will eat the spider mites.
We recommend to use Phyto mites:
In this overview we will help you diagnose, prevent and treat the most common plant diseases!
For all affected plants there's just one rule: separate them from your healthy plants to keep diseases from spreading.
1. MEALY BUGS (wolluis)
Small fuzzy white insects that look like cotton fluff.
Prevention : Try to weekly check your plants for bugs to prevent them from developing. Mealy bugs often appear when the air is very dry (both in summer and in winter when your heating is on) so regularly misting your plants to increase humidity will definitely help.
Very common on Palms, Cacti & Succulents.
Treatment : As soon as you spot a mealy bug, treat your plant immediately because they can spread quickly. A simple way is to remove adult bugs with cotton swabs (or an old tooth brush) soaked in alcohol or detergent. Make sure to rinse all the leaves with water afterwards (cover the soil with plastic while you're doing this). For larger infestations, it's best to use Chrysopa larvae that will eat the mealy bugs.
We recommend to use Chrysopa larvae:
2. SPIDER MITES (spint)
Super tiny spiders that leave very fine webbing on the leaves and stems of your plant. Leaves often look deformed, curled or change colour.
Prevention : Try to weekly check your plants for bugs to prevent them from developing. Spider mites also appear when the air is very dry (both in summer and in winter when your heating is on) so regularly misting your plants to increase humidity will definitely help.
Very common on Calathea & Alocasia.
Treatment : As soon as you spot spider mites, give your plant a good shower to rinse off all the bugs. Wipe down the leaves with a damp cloth and soap (cover the soil with plastic while you're doing this). It's also recommended to cut away the most affected leaves. For larger infestations, it's best to use predatory mites that will eat the spider mites.
We recommend to use Phyto mites:
3. FUNGUS GNATS (rouwvliegjes)
They look like small fruit flies, mostly flying around damp soil.
Prevention : Fungus gnats appear when the soil is too moist for a longer period of time. Make sure the soil can dry out (use terracotta pots instead of plastic pots) and remove standing water in saucers as soon as possible.
Treatment : These flies reproduce very quickly, they lay eggs in the soil so you have to get rid of both the adult flies as well as the eggs.
The best treatment is to dissolve nematodes in water and pour this on the soil. These nematodes are harmless for you or your plant, they will live for 4 weeks and eat all the larvae in the soil. You can additionally cover the top of the potting soil with sand to keep larvae from escaping.
We recommend to use biological Nematodes:
4. THRIPS (trips)
Very small, narrow and long insect that can also fly. Young insects are white and appear on the bottom of the leaves, grown insects are dark brown and can be found on top of new leaves. Because these insects suck the sap out of the leaves, yellow patches will appear that will turn brown over time.
The best treatment is to dissolve nematodes in water and pour this on the soil. These nematodes are harmless for you or your plant, they will live for 4 weeks and eat all the larvae in the soil. You can additionally cover the top of the potting soil with sand to keep larvae from escaping.
We recommend to use biological Nematodes:
4. THRIPS (trips)
Very small, narrow and long insect that can also fly. Young insects are white and appear on the bottom of the leaves, grown insects are dark brown and can be found on top of new leaves. Because these insects suck the sap out of the leaves, yellow patches will appear that will turn brown over time.
Prevention : Thrips are very difficult to treat because they seem to appear out of nowhere. Try to keep humidity high and keep plants away from draught to prevent them from getting pests.
Common on Monstera & other Philodendron species.
Treatment : Keep affected plants moist to limit damage, spray leaves with water on a daily basis. It's recommended to cut away damaged leaves. The best solution is to use predatory bugs that will eat the adult thrips as well as the larvae in the soil. (If you use insecticidal soap, this will only damage the adult thrips.)
We recommend to use Orius predatory bugs:
5. APHIDS (bladluis)
Aphids come in many different shapes and colours, they can be brown, green, orange, red,.. They also leave a sticky substance on the leaves.
Prevention : Aphids usually appear outdoors, but can easily come inside by sticking on clothing or through open windows. If you notice your outdoor plants are infested, it's best to keep your windows closed until after treatment.
Common on Ficus & Strelitzia.
Treatment : If you notice aphids on your plants, give your plant a good shower to rinse off all the bugs. It's also recommended to cut away affected leaves. The best way to get rid of these bugs, is to use larvae of the ladybug.
Common on Monstera & other Philodendron species.
Treatment : Keep affected plants moist to limit damage, spray leaves with water on a daily basis. It's recommended to cut away damaged leaves. The best solution is to use predatory bugs that will eat the adult thrips as well as the larvae in the soil. (If you use insecticidal soap, this will only damage the adult thrips.)
We recommend to use Orius predatory bugs:
5. APHIDS (bladluis)
Aphids come in many different shapes and colours, they can be brown, green, orange, red,.. They also leave a sticky substance on the leaves.
Prevention : Aphids usually appear outdoors, but can easily come inside by sticking on clothing or through open windows. If you notice your outdoor plants are infested, it's best to keep your windows closed until after treatment.
Common on Ficus & Strelitzia.
Treatment : If you notice aphids on your plants, give your plant a good shower to rinse off all the bugs. It's also recommended to cut away affected leaves. The best way to get rid of these bugs, is to use larvae of the ladybug.
We recommend to use Adalia larvae:
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Inspired by 'Houseplants for all' & "Het Plantenlab"