The Use of Insecticides as standard in bulb production
Every year when it gets to September the supermarkets and plant nurseries fill the shelves with bulbs marked as “Pollinator Friendly” or “Great for attracting pollinators”
This makes me see red as ALL these bulbs as standard have been drenched in insecticides such as neonicotinoides to deter aphids and often include a fungicide to prevent disease.
A standard bulb packet promoting attracting pollinators
It is very true that the flowers from these bulbs will attract insects but the use of neonicotinoides can have massive detrimental effects.
Direct Effects of Neonicotinoides on Insects are;
Lethal toxicity
Insecticides (especially systemic ones such as neonicotinoids) can kill non-target insects that come into contact with treated plants.
Pollinators such as bees, hoverflies, and butterflies may ingest pesticide residues through pollen or nectar.
Long term effects
Even when not fatal, low levels of pesticide exposure can impair insect navigation, memory, reproduction, and immunity.
Bees may have reduced foraging efficiency, weaker colonies, or increased vulnerability to disease.
The indirect effects on insects are
Loss of food sources
If pesticides reduce the abundance of aphids or other insects that serve as food, this affects predatory insects (e.g., ladybirds, lacewings, ground beetles).
Reduced pollination services
Decline in bee and hover fly activity lowers pollination of both wildflowers and nearby crops.
Contamination of soil and water
Systemic pesticides can persist in soil and spread to surrounding plants, exposing insects beyond the treated bulbs.
Specific Concerns with Flowering Bulbs
Timing: Spring bulbs often bloom when pollinators are emerging from winter and are in greatest need of nectar and pollen. Pesticide use at this stage can have outsized effects.
Systemic uptake: Many bulbs are treated before planting; systemic pesticides applied to bulbs can be transported into nectar and pollen months later when flowers bloom.
Cumulative impact: Repeated yearly treatment can build up residues in soil, affecting insect populations over time.
Ecological Consequences
Declines in pollinators (bees, hoverflies, butterflies).
Reduction in beneficial insect predators, leading to more pest outbreaks later.
Knock-on effects up the food chain (birds, small mammals) due to reduced insect availability.
To summarise:
Using pesticides on flowering spring bulbs can harm pollinators and beneficial insects through direct poisoning, sublethal effects, and food chain disruption. Because bulbs flower early in the season—when insects are most vulnerable—the ecological risks are particularly high.
The light at the end of the tunnel
There are a few pesticide free bulb suppliers. We use (and have always used) Peter Nyssen and have always been delighted with their selection and service. As an added bonus, all packaging is plastic free. We are not being paid for this post, I just feel very strongly about what they do. Crocus have a small selection and there’s a company called Organic Gardener which sell 100% organic bulbs.
One of the best things you can do is ask your supplier before buying, that way you are raising awareness that this is what the consumer wants.
Rant over and happy bulb planting x