Hyacinths crawling with flies

[WendyS]

Have just been given a bowl of hyacynths but after 48 hours in a warm room the compost is seething with tiny flies. I've put the bowl in the garden temporarily hoping the cold will kill them off but is there another quick and easy way of getting rid of the menace? I don't want all my other house plants infected.

[Thunderbird+]

Hi Wendy,
It sounds like the dreaded 'Fungus flies' aka Sciarid flies.
I think moving the plant outside may have been a wise move, as the flies could spread to other plants, so maybe the sacrifice will be worth it. the grubs mostly feed on the fine root haires and weaken the plant.
As for quik and easy ways of ridding them, I'm not so sure, they can be difficult but any house plant insecticide should control them, one that contains 'Permethrin' should help.
Good Luck Tbird+

[Hawkwalk]

They thrive in the wet so best to allow the compost to dry out on the surface and you will find they go away. Being a bulb it wont need much water and you can allow it to sit fairly dry. They will not do any harm to the hyacinth bulb and will not affect the flowering. Bring the plant back indoors when they have gone and you should be ok.

[Tigh]

They are harmless little flies that live in compost. They won't harm you or your plant; however putting the plant out in the cold is very likely to harm it. Bring it back indoors, and when you water it, add a small amount of insecticide to the water; that'll sort the problem.