Pest identification
What's eating my euphorbia milii 'lutea'?
Mealybugs
Signs: White waxy tufts in stem joints and around flower bracts; sticky honeydew and deformed new growth.
Control: Dab with isopropyl alcohol; spray with neem oil or insecticidal soap; repeat weekly until infestation clears.
Spider mites
Signs: Tiny pale flecks on leaves and bracts; webbing visible on the undersides in dry, warm conditions.
Control: Spray the whole plant — especially leaf undersides — with neem oil or a miticide; repeat every 7 days for three cycles.
Aphids
Signs: Soft-bodied green or black insects clustered on new shoot tips and flower buds; curling, sticky growth.
Control: Knock off with a strong water jet; apply insecticidal soap or neem oil spray; introduce ladybirds outdoors as a biological control.
Caterpillars
Signs: Irregular holes or notching in soft leaves; frass pellets visible near feeding sites on outdoor plants.
Control: Hand-pick caterpillars and egg masses; apply Bacillus thuringiensis (Bt) spray to foliage as a targeted biological control.
Keep euphorbia milii 'lutea' pest-free
Healthy plants resist pests best. Get the basics right:
Euphorbia milii 'Lutea' pests — FAQ
What is eating my euphorbia milii 'lutea'?
Euphorbia milii 'Lutea' (Crown of Thorns, yellow form) is grown indoors and outdoors and is attacked mainly by mealybugs and spider mites. Outdoors, aphids cluster on new buds and caterpillars may nibble soft leaves, but the spiny stems and latex limit damage. Mealybugs in stem crevices are the most consistent year-round threat.
How do I get rid of mealybugs on euphorbia milii 'lutea'?
White waxy tufts in stem joints and around flower bracts; sticky honeydew and deformed new growth. Dab with isopropyl alcohol; spray with neem oil or insecticidal soap; repeat weekly until infestation clears.
How do I get rid of spider mites on euphorbia milii 'lutea'?
Tiny pale flecks on leaves and bracts; webbing visible on the undersides in dry, warm conditions. Spray the whole plant — especially leaf undersides — with neem oil or a miticide; repeat every 7 days for three cycles.
How do I get rid of aphids on euphorbia milii 'lutea'?
Soft-bodied green or black insects clustered on new shoot tips and flower buds; curling, sticky growth. Knock off with a strong water jet; apply insecticidal soap or neem oil spray; introduce ladybirds outdoors as a biological control.
How do I get rid of caterpillars on euphorbia milii 'lutea'?
Irregular holes or notching in soft leaves; frass pellets visible near feeding sites on outdoor plants. Hand-pick caterpillars and egg masses; apply Bacillus thuringiensis (Bt) spray to foliage as a targeted biological control.