Scottish Rock Garden Club Forum

Bulbs => Galanthus => Topic started by: uvularia on January 13, 2014, 10:48:53 PM

Title: In fear of the Narcissus Fly
Post by: uvularia on January 13, 2014, 10:48:53 PM
I have to say that starting a collection of Galanthus is very exciting but after reading much about their cultivation, one starts to live in fear of the Narcissus Fly. Luckily my only losses to this creature is 'Brenda Troyle' and she is proving to be relatively vigorous. So not a disaster. But I would be upset if my less vigorous varieties were attacked. Apart from constructing a 'Narcissus Fly-proof' bulb house, can anyone suggest some simple ways of protecting individual clumps?
Title: Re: In fear of the Narcissus Fly
Post by: Alan_b on January 13, 2014, 11:11:37 PM
Systemic insecticide.

In principle you could construct covers for use when the flies are active.  Last year I covered a whole raised bed and a collection of pots with fleece from late May to late August.  Nothing has obviously suffered but it's way too soon to know if I have derived any benefit.  My concern was the Swift Moth, because their larvae have a voracious appetite for snowdrops.
Title: Re: In fear of the Narcissus Fly
Post by: Maggi Young on January 13, 2014, 11:22:21 PM
Kentish Lass has told us before of using upturned hanging baskets covered with  fine mesh or horticultural fleece to protect individual clumps.
As you might imagine, narcissus fly  features quite often in forum discussions - mostly with assorted expletives!
Title: Re: In fear of the Narcissus Fly
Post by: Maggi Young on January 13, 2014, 11:30:12 PM
Some of the threads showing  the worry of this pest!

http://www.srgc.net/forum/index.php?topic=204.0 (http://www.srgc.net/forum/index.php?topic=204.0)

http://www.srgc.net/forum/index.php?topic=3690.0 (http://www.srgc.net/forum/index.php?topic=3690.0)

http://www.srgc.net/forum/index.php?topic=9919.0 (http://www.srgc.net/forum/index.php?topic=9919.0)
http://www.srgc.org.uk/smf/index.php?topic=4405.0 (http://www.srgc.org.uk/smf/index.php?topic=4405.0)

http://www.srgc.org.uk/smf/index.php?topic=4297.0 (http://www.srgc.org.uk/smf/index.php?topic=4297.0)    lesser narcissus fly

http://www.srgc.org.uk/smf/index.php?topic=1850.0 (http://www.srgc.org.uk/smf/index.php?topic=1850.0)

Title: Re: In fear of the Narcissus Fly
Post by: uvularia on January 13, 2014, 11:39:02 PM
Thanks Maggi! That is a few threads to have a look through!
Title: Re: In fear of the Narcissus Fly
Post by: Maggi Young on January 13, 2014, 11:45:17 PM
Don't do it all at once, Paul - you'll depress yourself.   Though reading of Martin Baxendale patrolling his garden with a tennis racquet to swat 'em is quite amusing!

So many references in the forum - amazing what the little blighters can chomp their way through. 

Alan B. and others also speak of the danger from Swift Moth caterpillars -  let's face it - sometimes it seems there are armies of munching enemies  in the garden, just waiting to ruin our day.
Title: Re: In fear of the Narcissus Fly
Post by: GordonT on January 14, 2014, 12:22:27 AM
Sorry - I oughtn't to have posted this under Galanthus... it is just that bulb flies managed to ruin a large part of our future garden plans. Last year we gave up entirely on growing any Narcissi in our gardens. We bought a lot of Narcissus 'Ice Follies' in the autumn of 2012, and they made an impressive show in May last year. During garden expansion after the foliage had died down, I realised that I had to regroup the Narcissi. Every one of the bulbs was fly blown! The blighters didn't spare a single one. I checked all of our other plantings and all bulbs had been ruined.

I'll take my chances with Tulips and White Tailed Deer rather than attempting Narcissi again! :-X
Title: Re: In fear of the Narcissus Fly
Post by: mark smyth on January 14, 2014, 12:33:45 AM
Thankfully last year until July was too cool  for them to be active. Fly swats! I keep about four in the garden and one in the back pocket. Hit them hard! They like to bask on stones and large leaves. Every one I kill I give it a squeeze. If an ovipositor pops out I'm very happy.

Systemic pesticides all the way

and learn how to tell them from the good guys
narcissus fly Merodon equestris (http://www.youtube.com/watch?v=1zqxbuSeIx8#)
narcissus fly Merodon equestris (http://www.youtube.com/watch?v=j7ppPND_LCc#)
Title: Re: In fear of the Narcissus Fly
Post by: Alan_b on January 14, 2014, 08:16:35 AM
Narcissus flies come in from the top of the bulb and the entry wound should be obvious if you lift and divide your bulbs when dormant.  If you cut-open the bulb (or the remaining husk) then the fly larva should still be inside.  Therefore an effort-intensive way of dealing with the flies is to lift your bulbs when dormant and check for entry wounds.  This is easiest if you plant your snowdrops in lattice pots.  Obviously this doesn't much help the bulbs but reduces the numbers in the next generation of flies.

Swift moth larvae attack from the side or the base and I think they will also eat the large roots during the growing season.  They sometimes eat only some of the bulb and move-on so some bulbs survive an attack and eventually recover.  I suspect that they are particularly attracted to snowdrops as I have lost snowdrops from amongst other bulbs.  I don't know whether they emerge from the soil at all until they pupate so I am trialling lattice pots as a means of restricting their movements, as all the well-fed larvae I find are too large to fit through the holes in a lattice pot.  The moths are supposedly active from June to August and they lay eggs on the wing therefore any protective covering would need a very fine mesh to prevent the eggs dropping through.  I also treat my soil with Nemasys 'Grow your own Nematodes', being the best hope I can find of achieving a biological control.

Edit: Good note on Swift Moths here: http://www.donsgarden.co.uk/pests/538?telephone=5 (http://www.donsgarden.co.uk/pests/538?telephone=5)     
Title: Re: In fear of the Narcissus Fly
Post by: uvularia on January 14, 2014, 10:04:25 AM
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...



Title: Re: In fear of the Narcissus Fly
Post by: Anthonyh on January 14, 2014, 12:04:24 PM
Like Alan, I'm experimenting with covering some of my snowdrops. I have a couple of frames with shade net sides and I put 'wondermesh' (I scrounged some from a friend) over the top during the summer. All tightly sealed.  Only the second year of use, but no sign of trouble yet (although I do worry that if they get in, and get trapped, they could go wild in the frames).

Until recently I hadn't had much trouble, but I had some mushroom boxes full of nivalis I didn't get round to planting out- the Narcissus fly loved those, I assume because they were relatively shallow planted and concentrated in a small area. I had to go through every bulb to check them in the hope of preventing grubs reaching maturity.

I've tried a few insecticides, and I'm a bit sceptical about how effective they are, but I don't have much evidence either way as it's pretty hard to do controlled experiments.  .
Title: Re: In fear of the Narcissus Fly
Post by: mark smyth on January 14, 2014, 12:24:09 PM
Narcissus fly don't care if snowdrops are grown in full sun or full shade. They still go for them
Title: Re: In fear of the Narcissus Fly
Post by: ChrisD on January 14, 2014, 09:20:58 PM
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...

A couple of comments; firstly in my garden Galanthus generally dont grow well in positions where they dont get any winter sun. The soil here is very heavy and I suspect tat it is just too cold and wet for them to thrive.

Secondly I would be tempted to try the biological controls as they certainly wont do any harm, however I suspect they wont be very effective either. The Bacillus protein needs to be eaten by the larvae to be effective, it is difficult to see the larvae eating any as it chomps its way through the stem and into the bulb. The nematodes may be too specific, I guess they will attack vine weevils and nothing else.

Sorry to be so negative

Chris
Title: Re: In fear of the Narcissus Fly
Post by: Martin Baxendale on January 14, 2014, 09:44:24 PM
I've started using a cheap children's seaside fishing net (the kind with a small net on the end of a bamboo cane) to catch narcissus fly as they settle on snowdrop leaves, then squish them in  the net. It causes less damage than lashing out with my old tennis racket near snowdrop leaves.
Title: Re: In fear of the Narcissus Fly
Post by: uvularia on January 14, 2014, 10:56:59 PM
I've started using a cheap children's seaside fishing net (the kind with a small net on the end of a bamboo cane) to catch narcissus fly as they settle on snowdrop leaves, then squish them in  the net. It causes less damage than lashing out with my old tennis racket near snowdrop leaves.

Would you get more control with a squash racket? Useful in tight corners?
Title: Re: In fear of the Narcissus Fly
Post by: Martin Baxendale on January 14, 2014, 11:07:54 PM
My daughter won't let me use her squash racket  :)
Title: Re: In fear of the Narcissus Fly
Post by: RichardW on January 15, 2014, 10:05:30 AM
A couple of comments; firstly in my garden Galanthus generally dont grow well in positions where they dont get any winter sun. The soil here is very heavy and I suspect tat it is just too cold and wet for them to thrive.

Ditto, in fact the areas that are very shady are now only really planted with lattice pots.

I'm fairly philosophical about bugs and beasties, I have lost nice bulbs to both over the years but have to accept it, particularly in a garden of 7 acres surrounded by lots of wildlife that isn't always welcome. Virtually All my new acquisitions go into lattice pots for a few years to bulk up, have found this works very well, gives some protection, good growing conditions and not lost anything yet.
Title: Re: In fear of the Narcissus Fly
Post by: Alan_b on January 15, 2014, 12:01:03 PM
Just to clarify, I presume Richard uses lattice pots primarily to replace his normal heavy clay soil with a mixture better-suited to snowdrops.  I myself have tended to use raised beds to control the growing medium but still have lattice pots to confine the snowdrops to a well-defined location and in the hopes that they provide protection against predators.  So whilst many of us use lattice pots, we don't all do so for the exactly same reasons.
Title: Re: In fear of the Narcissus Fly
Post by: RichardW on January 15, 2014, 12:21:33 PM
Yes sorry I'm also on heavy clay so use a free draining mix to give them a better chance.

even in the areas where the soil conditions are better I'm still using them after a few years of trials, there are a few downsides but for new bulbs especially singles I think they are well worth using.
Title: Re: In fear of the Narcissus Fly
Post by: uvularia on January 15, 2014, 08:08:42 PM
So, Richard, do you just bury the lattice pots filled with free-draining compost in the clay soil?
Title: Re: In fear of the Narcissus Fly
Post by: RichardW on January 15, 2014, 08:28:30 PM
Yes, mix is John Innes, general purpose compost, sharp sand and fine well rotted leaf mould, some are also sitting on pea shingle/sharp sand to give extra drainage & prevent a pan forming under the pot. Results have been very good & I'm sure some varieties I struggle with wouldn't be here/doing so well without them.
Title: Re: In fear of the Narcissus Fly
Post by: Lesley Cox on January 16, 2014, 12:26:08 AM
I have to agree with Mark that systemic insecticides are the only real way to keep narcissus fly out of all plantings of Amaryllidaceae. Spraying of the foliage as it emerges then further sprays through the season is effective but also, so is the fingering in around the clumps of insect-repelling granules such as Diazanon, Carbaryl and others. suSCon green is also very good and works totally. One needs to remember though that these chemicals are not only very dangerous to other insects and wildlife but to humans and pets. Many are now banned for use by home gardeners anyway. We in NZ have a systemic insecticide/fungicide called Shield, mainly for use on roses. It works well and is, I suppose, relatively safe.

I do think one needs to take some measures to protect plantings in the small garden situation. Learning to live with some of the pests may be a solution for large gardens where the bulbs may be present in many hundreds or thousands but when one has a few pots or garden clumps, it doesn't take many narc fly to deplete one's stock altogether. The swatting option is fine for those seen but how many flies go unseen or missed? As well as removing dead foliage, the surface of the compost/soil around the clumps or on top of pots should be well disturbed and fingered or forked over so that there are no obvious entry points. Holes show the way though I suspect a fly could get into the tiniest space in search of its quest to populate the earth.
Title: Re: In fear of the Narcissus Fly
Post by: Diane Whitehead on January 16, 2014, 12:54:45 AM
I've planted hundreds of narcissus, none of which survived.  However, there
is one area where they have multiplied prodigiously.  I finally figured out why.
The ground is thoroughly infested with one of our natives, Vancouveria hexandra,
despite my having attempted destruction of it every year for several decades.
This plant's roots are filling every bit of the soil from the surface down a garden
fork's depth.  It is deciduous in winter, but very leafy the rest of the year. The
daffodils come up through it easily, but the fly is obviously deterred.
Title: Re: In fear of the Narcissus Fly
Post by: Alan_b on January 16, 2014, 09:56:01 AM
I find it odd that we have two reports of narcissus fly attack from opposite sides of Canada but in both cases so severe as to destroy the narcissus population.  To me this raises the question of what is sustaining the fly population?  Do they turn their attention to some indigenous Canadian bulb in the absence of narcissi?  Otherwise how could they be present in such large numbers?     
Title: Re: In fear of the Narcissus Fly
Post by: Maggi Young on January 16, 2014, 11:08:49 AM
The little blighters are happy to chomp other amaryllids -
http://pacificbulbsociety.org/pbswiki/index.php/NarcissusBulbFly (http://pacificbulbsociety.org/pbswiki/index.php/NarcissusBulbFly) - so who knows what they may adapt to  if need be?  :P
Title: Re: In fear of the Narcissus Fly
Post by: emma T on January 16, 2014, 11:11:51 AM
I wonder if I could train my dogs to sniff out fly infested bulbs ?
Title: Re: In fear of the Narcissus Fly
Post by: Maggi Young on January 16, 2014, 11:36:35 AM
I wonder if I could train my dogs to sniff out fly infested bulbs ?

Yes, seriously, Emma, it should be perfectly possible to train a dog to do that - if they can be trained to detect, cancers, explosives, drugs, money, truffles -    manky bulbs  should be a doddle.
Title: Re: In fear of the Narcissus Fly
Post by: Alan_b on January 16, 2014, 12:05:54 PM
I wonder if I could train my dogs to sniff out fly infested bulbs ?

I thought of a similar idea a year or two ago that I might have mentioned here - but I don't have a dog with which to put it into practice.  When bulbs are damaged by disease or insect attack they frequently rot.  If you dig-up a rotting bulb then the smell is very strong indeed so I thought a trained dog should be able to identify such a bulb whilst it was still in-situ.     
Title: Re: In fear of the Narcissus Fly
Post by: mark smyth on January 16, 2014, 01:32:33 PM
A couple of comments; firstly in my garden Galanthus generally dont grow well in positions where they dont get any winter sun. The soil here is very heavy and I suspect tat it is just too cold and wet for them to thrive.

About half of my collection are in the beds and troughs at the back of the house where they will get no sun until maybe March
Title: Re: In fear of the Narcissus Fly
Post by: johnw on January 16, 2014, 02:22:02 PM
  To me this raises the question of what is sustaining the fly population?  Do they turn their attention to some indigenous Canadian bulb in the absence of narcissi?  Otherwise how could they be present in such large numbers?

Alan:

Simple.  Annual Dutch imports by the boatload.  I suspect here it is mainly an urban problem for the time being.  As well we import many Narcissus from BC.

johnw     - +5c and drizzle.
Title: Re: In fear of the Narcissus Fly
Post by: Diane Whitehead on January 16, 2014, 04:47:13 PM
And in British Columbia we have fields of them because they flower here early and are
shipped by air to the rest of Canada still in the icy grip of winter.
Title: Re: In fear of the Narcissus Fly
Post by: ChrisD on January 16, 2014, 08:02:20 PM
About half of my collection are in the beds and troughs at the back of the house where they will get no sun until maybe March

Mark - I guess your soil is not a heavy clay? I suspect it is the soil temperature or something similar that means snowdrops dont thrive in the shady parts of my garden. I also suspect that some varieties would have no problems with these conditions but the ones I tried either died in their first season or gradually decreased in vigour until they were moved to a more favourable location.

Chris
Title: Re: In fear of the Narcissus Fly
Post by: Alan_b on January 16, 2014, 11:17:03 PM
So we must be saying that every year in Canada large numbers of narcissi are imported then left in the ground after flowering.  These are then infected by the narcissus fly which destroy those bulbs but when the larvae pupate the following year they have next years imports to infect.  The large quantities of imports mean that a much larger population of narcissus flies can be sustained than would be the case in a more static narcissus population, such as exists here in the UK.
Title: Re: In fear of the Narcissus Fly
Post by: johnw on January 17, 2014, 12:35:32 AM
So we must be saying that every year in Canada large numbers of narcissi are imported then left in the ground after flowering.  These are then infected by the narcissus fly which destroy those bulbs but when the larvae pupate the following year they have next years imports to infect.  The large quantities of imports mean that a much larger population of narcissus flies can be sustained than would be the case in a more static narcissus population, such as exists here in the UK.

For here Alan not exactly, there is never 100% kill of Amaryllidaceae here, if one plants a hundred bulbs you may lose a few but never everything, oftentimes nothing.  Newfoundland is different, bulbs get wiped out completely so there I assume the Dutch supply next year's victims.  Maybe Howard can confirm that this is indeed the case there.

When I dig 500 snowdrops about 20 maybe will have active larvae inside.  It's a manageable sitaution here in NS.  My guess is it's much the same in Ontario. 

BTW the pheasant's eyes are late enough to miss the NBF cycle.

johnw - the seedex goodies arrived today.
Title: Re: In fear of the Narcissus Fly
Post by: Diane Whitehead on January 17, 2014, 04:08:52 AM
I notice many patches of Galanthus elwesii along the roads as I walk in my neighbourhood.
They are usually near a tree trunk, but I guess that doesn't mean much since we have so
many trees they'd have a hard time being somewhere else.  They don't seem to suffer any
depredation by the fly.  They are not the only plants in their spots, of course.  There are ferns,
and grasses since the roadsides get a fair bit of light.  I think these "companion plants" are
the key.  The fly  looks for the interface of narcissus or galanthus leaves with the soil, and
if this is hidden by broad leaves of some sort, the fly doesn't lay its eggs.

So, if you are going to grow your snowdrops in pots, drop a lettuce seed beside the leaves.
It will be leafy enough for protection by the time the fly comes by, and after fly season,
you can have a salad.

Title: Re: In fear of the Narcissus Fly
Post by: Tim Ingram on January 17, 2014, 09:21:57 AM
It must be rather similar in naturalised populations of snowdrops like these in Lorenden Woods near to us. After the snowdrops flower there are naturalised narcissi and then bluebells, and after this nettles and stronger growing perennials. The simple message is that if you want your garden to prosper let it run a little wild - which is a slight anathema to a tidy mind.
Title: Re: In fear of the Narcissus Fly
Post by: Alan_b on January 17, 2014, 12:29:16 PM
I started a topic last year on summer companion plants for snowdrops http://www.srgc.net/forum/index.php?topic=10365.0 (http://www.srgc.net/forum/index.php?topic=10365.0) prompted by the observation that stinging nettles seem to be quite good.  At the moment I am trialling an attractive dead nettle (I think I chose Lamium orvala as per Darren's suggestion) but so far only to the point of seeing if it will actually grow in my dry garden.
Title: Re: In fear of the Narcissus Fly
Post by: Tim Ingram on January 17, 2014, 01:43:34 PM
Alan - you shouldn't have any trouble with Lamium orvala in a dry spot. I've been trying to get rid of it seeding along the south side base of a sleeper bed for alpines. It has very deep questing roots. I am very tempted now to follow your example and plant it with some of the snowdrops! This is just going some of the way to the wonderful tapestry of woodland perennials that you see in gardens like Sissinghurst, Knightshayes Court, Beth Chatto's, and one (I think) up in Aberdeen!
Title: Re: In fear of the Narcissus Fly
Post by: Lesley Cox on January 17, 2014, 09:41:29 PM
  If you dig-up a rotting bulb then the smell is very strong indeed so I thought a trained dog should be able to identify such a bulb whilst it was still in-situ.     

And such a disgusting smell too. Just what dogs like. :o

I hate to suggest it but is it possible that these large importations of bulbs, (presumably from Holland?) are already hosts to the fly larvae? They would be invisible from a visual search and it takes quite a firm squeeze to detect the telling softness of the bulb which is typical of the larvae presence.
Title: Re: In fear of the Narcissus Fly
Post by: Hagen Engelmann on April 26, 2015, 07:31:13 PM
I put out the snowdrop leaves in the moment. So narcissus flies will not find the way to the bulbs. It is OK, because the leaves soak off on the neck of the bulbs. If you like your snowdrops start your activities to protect the plants.
Title: Re: In fear of the Narcissus Fly
Post by: Hagen Engelmann on May 03, 2015, 07:19:47 PM
They are flying now!!!  >:( :(
Title: Re: In fear of the Narcissus Fly
Post by: mark smyth on May 03, 2015, 10:14:40 PM
Too cold here just now thankfully. Leaves are now dying fast which is good
Title: Re: In fear of the Narcissus Fly
Post by: Ant-k on February 07, 2016, 06:00:25 AM
As a reliative new comer to galanthus it is with much horror I have come across my first dealings with the dreaded narcissi fly and it's off Spring!.. But thinking back I probably had been 'attacked'by one on a small group of 'Trumps' about 3 years back as all but 1 of a small set of bulbs I bought came up  flowering as normal and the other had a few wispy leaves which I can now say after 3 years is back flowering and multiplied well.
This year had the same problem on a 'Trym' clump so decided to dig it up and found the bulb had been partly eaten and loads of little bulb lets had started to grow..any way after reading all the articles on this forum it does make you worry a little.I must admit the two attacks seem to have been where the drops had no cover from the many hostas I grow and had been left exposed,so my question after waffling on is at what point can you safely  cut leaves off your galanthus without it having a effect on the health of the bulb and before the fly is active? and is this a recommended ploy any forum members use?
Title: Re: In fear of the Narcissus Fly
Post by: mark smyth on February 07, 2016, 11:36:23 AM
I only remove leaves when they have turned yellow and starting to dry or rot if its wet
Title: Re: In fear of the Narcissus Fly
Post by: Olive Mason on February 07, 2016, 12:32:40 PM
As a reliative new comer to galanthus it is with much horror I have come across my first dealings with the dreaded narcissi fly and it's off Spring!.. But thinking back I probably had been 'attacked'by one on a small group of 'Trumps' about 3 years back as all but 1 of a small set of bulbs I bought came up  flowering as normal and the other had a few wispy leaves which I can now say after 3 years is back flowering and multiplied well.
This year had the same problem on a 'Trym' clump so decided to dig it up and found the bulb had been partly eaten and loads of little bulb lets had started to grow..any way after reading all the articles on this forum it does make you worry a little.I must admit the two attacks seem to have been where the drops had no cover from the many hostas I grow and had been left exposed,so my question after waffling on is at what point can you safely  cut leaves off your galanthus without it having a effect on the health of the bulb and before the fly is active? and is this a recommended ploy any forum members use?
Title: Re: In fear of the Narcissus Fly
Post by: johnstephen29 on February 07, 2016, 03:02:23 PM
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.
Title: Re: In fear of the Narcissus Fly
Post by: colineddie1 on March 19, 2016, 01:49:41 PM
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...
Title: Re: In fear of the Narcissus Fly
Post by: MargaretB on March 19, 2016, 02:28:17 PM
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.
Title: Re: In fear of the Narcissus Fly
Post by: mark smyth on March 19, 2016, 05:00:06 PM
Its not true that Narcissus fly do not like shade
Title: Re: In fear of the Narcissus Fly
Post by: Maggi Young on May 25, 2016, 05:08:50 PM
Picture by John Aipassa today on social media ....
[attachimg=1]
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."

Title: Re: In fear of the Narcissus Fly
Post by: Ian Lumsden on February 21, 2018, 03:52:42 PM
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.
Title: Re: In fear of the Narcissus Fly
Post by: Ken Devine on November 06, 2020, 03:39:53 PM
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 ?
Title: Re: In fear of the Narcissus Fly
Post by: Michelle Swann on May 24, 2021, 09:11:58 AM
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
Title: Re: In fear of the Narcissus Fly
Post by: Alan_b on May 24, 2021, 09:27:06 AM
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.
Title: Re: In fear of the Narcissus Fly
Post by: Tim Harberd on June 11, 2021, 12:20:27 AM
I lost a  LOT  of Daff bulbs to grubs last year. Quite depressing/dis-spiriting.

Iíve 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.
Title: Re: In fear of the Narcissus Fly
Post by: Tim Harberd on July 17, 2021, 11:38:00 AM
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
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