In fear of the Narcissus Fly

[johnstephen29]

I've been reading with interest the posts on here about the narcissus fly, to be honest I can't say hand on my heart wether I've seen one or not. They don't seem to be a problem here, I grow various amaryllis relatives and none that I know of seem to be affected. Galanthus, narcissus, amaryllis, crinum all grow ok, having said that I did bring some narcissus st Patrick's day bulbs down from Yorkshire when we moved here and they did well at first the gradually disappeared so I don't know.

[colineddie1]

Thought I would check out MET52 - they say its being discontinued and the only place I can find on Ebays is from America - and the price has just made my eyes water - well gonna try a couple of other things - hope I can find something that works for both stag and fly

Thanks folks! Excellent info! Sounds like I need to stock up on Systemic Pesticide? Is there a particular one that works well?

I did read that Galanthus grown in permanent shade were less likely to get attacked? So I have gone for a north wall. Not the best place to show them off?
Does anyone think this works? I will definitely be clearing away old foliage.

I wonder if Bacillus thuringiensis would work as a biological control or Nematodes aimed at Vine Weevil? I prefer biological control. I use MET52 as standard in my compost to control Vine Weevil but not sure if the nematodes would go for Narcissus Fly larvae as well?

The sun is out! So time to take some photos...

[MargaretB]

I've used MET 52 in my potting compost for three years and it is excellent for keeping vine weevils away.  It doesn't seem to have any effect on narcissus fly though and I have lost several snowdrops from damage by the little devils.

[mark smyth]

Its not true that Narcissus fly do not like shade

[Maggi Young]

Picture by John Aipassa today on social media ....

John Aipassa‎ -
"Caught in the act. Laying eggs that is. Both are a bit stunned after smacking them on their heads. After taking the photo they went to fly heaven."

[Ian Lumsden]

That photograph of the narcissus flies made me shudder, Maggi. Last year I killed a few though it's impossible to mount guard on all the bulbs. This year 'Elizabeth Harrison' failed to show. The bulbs were in a large pot with sharp gravel layered on the top. The bulbs were completely gone with only some dried up mess left behind plus the grubs. I wish I had taken a photograph but seeing as the cultivar is or was a treasure I just ditched the compost after killing the grubs. I have decided to always grow the more expensive bulbs in different pots or parts of the garden - if I have more than one bulb - and completely change the compost at least every two years. I'm also going to place mesh over the best varieties. Better to be unsightly than in mourning. I'll never re-use potting compost again - into the heap.

[Ken Devine]

A couple of clumps of snowdrops (G. Atkensii and G. cordelia) appeared reduced last winter (end of January) so I dug up the bulbs to discover that a good number of bulbs had been infected by the narcissus fly with grubs (larva) still in situ. I pushed the grubs out through the neck of the bulb with a wire, destroyed the grubs and examined the remaining bulbs. If you look at the first picture of the G. Atkensii bulbs (2 grubs on the left hand side of the photo)  you can see that the basal plate at the bottom of each bulb is completly destroyed, however, what caught my eye was what looked like bulblet formation on the side of some of the bulbs. I cleaned all the bulbs regardless of condition and placed them in wetted vermiculite in a warm dark sport to see what would happen. 8 weeks later it was clear that bulblet formation continued on the sides of some of the bulbs, I assume regenerating from the lateral meristem (see bulblet formation photo). The question is can these bulblets eventually produce leaves and new plants. It's well know that you can get new "grass like" snowdrop leaves emerging the following season after narcissus fly infestation - I assummed this would only occur in bulbs where some of the basal plate was remaining (see G. cordelia bulblet regeneration from the basal plate photo after narcissus fly destruction). Has anybody every seen bulblet formation on the side of the bulbs before ? and what's your explanation ?

[Michelle Swann]

Hi Everyone,

I have to admit I am a bit of a Narcissus fly virgin and only after starting to just collect snowdrops last year is it a worry, I will be reading through all your posts later and the threads that Maggie posted. 

I never really invested heavily into loving my bulbs, but snowdrops are really catching my eye - but as you all know they come with a price tag, which means I will be more invested in caring for them - they will be getting almost as much pampering as my Trilliums lol.

Anyway, I am sure when I have read it all I will be horrified, I think I will approach one fear at time, next will be the fungal diseases and I will scare myself half to death with that too.

I love all my plants and try to save them regardless of cost as I hate to see any plant die, but snowdrops are too expensive to lose.

Thanks everyone.

Michelle x

[Alan_b]

There are two insects that particularly prey on snowdrops when in the larval form, the Narcissus Fly and the Swift Moth.  The former has received a lot more publicity than the latter but either can strike.  Their prevalence seems to depend on where you live.  Swift moth larvae live in the soil, have a taste for snowdrops but also other bulbs or plants with fleshy roots.  Their prevalence probably depends on soil conditions.  Narcissus Fly larvae live inside the bulb and prey on Narcissus and Galanthus so their prevalence probably depends on the density of host plants in the area.

[Tim Harberd]

I lost a  LOT  of Daff bulbs to grubs last year. Quite depressing/dis-spiriting.

I’ve never knowingly seen a bulb fly, so I put some of the affected bulbs in a jam jar, with a bit of soil and sealed the top with polythene plus rubber bands.

Imagine my surprise this week when two large black weevils were crawling around under the polythene.

[Tim Harberd]

Caught a third weevil in the jam jar today.

SO: My conclusion is that the "Grub Inside Bulb" problem is not Bulb Fly. At least not in my garden.

Now that I know my enemy, I can plan a campaign!

Tim DH