Stagonospora infection - collected threads

[steve owen]

Alan

I too have had to battle various bulb infection problems. As members may recall I had a major programme in the spring involving the raising, treating and replanting of around 400 varieties. Not an exercise to be done too often! My approach was to dig the bulbs up, strip off the infected outer scales (even though that may mean drastically reducing the size of the bulb - I think I followed advice from Martin or someone else who knew what they were doing) soak the remaining bulbs for at least two days in a mixture of strong disinfectant and fungicide, and then replant them in fresh potting mix in a lattice pot. The site from which they came gets a drench of similar mixture and then left empty of snowdrops. The lattice pots went back in the ground in fresh sites.

I don't know but guess that probably Matt B may have faced a similar exercise a few years ago when he had problems with stag. I have written to Matt because it would be really instructive to have his comments on this topic.

I think the scale stripping has to be fairly ruthless even if one is only left with a pretty thin central "stalk". The reduced size treated bulbs obviously need to be cosseted with a feeding regime to support their growth after their near death experience. Throwing away the bulbs is obviously an option of last resort, to be avoided if possible if the variety is a rare or valuable one.

The result has been visible control of the stag browning, at the cost of weaker growth from the reduced size bulbs. Its not a complete 100% effective cure; most of the treated pots show healthy growth, but a minority still show ill-health, and may need repeat treatment. Another result is that the growth of the treated bulbs is checked for about five or six weeks.

As I have posted previously, I also have a routine of preventative spraying of the snowdrops in growth and when dormant with strong disinfectant.

I would be interested to hear whether your approach of leaving the marked scales on and treating with jungle juice does seem to do the trick and over what period.

The two native English snowdrops (nivalis and flore pleno) seem by comparison to be as tough as old boots, and there is probably a decent research project to be had by some bright young botanist into how the newer galanthus hybrids are more prone to disease, and which are more susceptible. For example, are the yellows or limey yellows more liable to disease and more difficult to grow healthily than others? Maybe the Snowdrops 2 book will carry this discussion forward.

Steve

[mark smyth]

I am wondering if it would be worth spraying the snowdrops once the flowers are over and just as the Narcissus Fly are around - which I gather will be earlier this year? 

the fly is never very early in UK/Ireland

[ChrisD]

I am just catching up on older posts and was drawn to this product called 'Garlic Wonder' and have ordered some from Amazon.
I used to bubble up my own concoction but the smell in the kitchen was just too much! I generally use it to deter slugs from the early growth on my daylilies but recently growers have been recommending it for deterring daylily gall midge which is a real pest.

I am wondering if it would be worth spraying the snowdrops once the flowers are over and just as the Narcissus Fly are around - which I gather will be earlier this year?  The trouble is - once it rains it gets washed off.


Alan - did you work out a dilution rate and what are you using yours to prevent (hopefully) ? 

Jennie

Jennie
Are you thinking that the smell of garlic will mask the "smell" of the snowdrops and so prevent problems? That would be my assumption, and if correct it is likely that a raw and unprocessed garlic would be more effective than a dried preparation, it will be smellier. You could try one of the "easy garlic" purees from the supermarket diluted and watered into the soil around the drops. Unlikely to do any harm (in my opinion)
Chris

[daveyp1970]

I am just catching up on older posts and was drawn to this product called 'Garlic Wonder' and have ordered some from Amazon.
I used to bubble up my own concoction but the smell in the kitchen was just too much! I generally use it to deter slugs from the early growth on my daylilies but recently growers have been recommending it for deterring daylily gall midge which is a real pest.

I am wondering if it would be worth spraying the snowdrops once the flowers are over and just as the Narcissus Fly are around - which I gather will be earlier this year?  The trouble is - once it rains it gets washed off.


Alan - did you work out a dilution rate and what are you using yours to prevent (hopefully) ? 

Jennie

Jennie
Are you thinking that the smell of garlic will mask the "smell" of the snowdrops and so prevent problems? That would be my assumption, and if correct it is likely that a raw and unprocessed garlic would be more effective than a dried preparation, it will be smellier. You could try one of the "easy garlic" purees from the supermarket diluted and watered into the soil around the drops. Unlikely to do any harm (in my opinion)
Chris

or could you not plant your snowdrops with an allium that comes into leaf as the snowdrops are finishing flowering as to mask the smell as well.Companion planting is used to deal with other pests.

[Alan_b]

I thought I would record a note of various treatments that are commercially available for garden use I have tried to ward-off or prevent ill-health in snowdrops.  I have not conducted any sort of controlled trials so it is difficult to say what, if anything, is effective but in one instance I noticed an adverse reaction which I think is worth recording.

Treatments are as follows:

1.   “Natures Answer Natural pest and Disease Control” manufactured by The Scotts Company (UK) Ltd.
Sold as an insecticide and fungicide this is a spray containing sulphur in fatty acids.  I have used this for about 8 years to spray snowdrop bulbs when re-potting, particularly bulbs showing signs of ill-health or damage.  I’m not sure if this does any good but I have used it enough to be confident it does not do any harm.

2.   “Citrox” Manufactured by Agralan
This is sold as a disinfectant that if safe for use with plants.  I used the concentrate “Citrox P” which you dilute 150:1 with water to treat bulbs when re-potting but ran into problems.  I tried soaking the bulb and roots, in some instances overnight before potting-up the following day.  But I found those plants that had a prolonged exposure to Citrox during February 2011 became flaccid and died-back prematurely in March.  Other bulbs left overnight in tap water did not suffer.   

3.   “akTRIvator” manufactured by Canna, Holland. 
This is a water-soluble powder containing Trichoderma Harzianum fungus.  Sold as an aid to the development and root growth of cuttings it is supposed to suppress other fungi, specifically botrytis.  I treated many of my snowdrops with a small quantity of this in 2011 without any apparent harm.  I have never had a problem with botrytis (thank heavens) so I don’t know if it does any good.

4.   “Garlic Wonder” manufactured by Aston Horticulture.
Sold as a “plant stimulant” containing “natural garlic juice” you are instructed to dilute 1:10 with water and apply as a spray.  I am trialling this in 2012 following suggestions that garlic preparations may be effective against Stagonospora curtisii.

All the above are commercially available in the UK; although probably not from your local garden centre.  I would be interested to hear if anyone else has tried these products or had success with others (preferably excluding those that are now banned or only available for agricultural use).       
 

[chasw]

Alan can you tell me at what time of year you used the Trichoderma? Just wondering if it is more effective at certain times of the year
I did purchase a small amount last year ,but as yet have not used it

[Alan_b]

I used it in February and March, which was probably wrong because I'm not sure the temperature at that time of year is warm enough for it to thrive.  On the other hand, if it's warm enough for botrytis then maybe it's warm enough for Trichoderma.     

[Martin Baxendale]

I used it in February and March, which was probably wrong because I'm not sure the temperature at that time of year is warm enough for it to thrive.  On the other hand, if it's warm enough for botrytis then maybe it's warm enough for Trichoderma.     

It's warm enough this year.

[kentish_lass]

Funny you should mention companion planting with Alliums as that is exactly what the daylily society is suggesting as a preventative for gall midge.  Many people who have planted Alliums among their daylilies have noticed a reduction in gall midge attack.  However, all my snowdrops are now being planted under deciduous trees so I don't think an Allium would flower very well under those conditions.

When I have sprayed daylily foliage in the past with the garlic solution they seem to look healthier.  I think garlic is a good feed for most plants - it may be different for bulbs?

Good luck with your trial Alan.  Let us all know how you get on.  I prefer to go organic wherever possible.

Jennie

[Alan_b]

Some years ago, more by accident than design, I grew some damaged snowdrops in a pot alongside some small weedy white bulbs in the Allium family.  The snowdrops thrived and made a full recovery but these Alliums would probably out-compete the snowdrops if left to their own devices.

[Mavers]

Thanks for this info Alan.

Does anyone know if Neem Oil detrimental to snowdrops?

I grow quite a few of my snowdrops around & under climbing roses & have been advised to spray my roses with Neem to control disease.

[Jo]

Ha ha Alan,

 I just spotted this thread and assumed that at last there was a treatment for my galanthomania so I would therefore be able to save a fortune this year 

[kentish_lass]

Last year in desperation I used PRAVADO Ultimate Bug Spray in a ready made spray bottle.  I sprayed all the foliage of the snowdrops (and a couple of Lilium that were emerging).  I made sure the flowers were over so I would not be killing any bees or other insects - although I am sure a few still got killed 

The Lilium did not get any Lily Beetle last year except the Martagons that I forgot to spray.  They say one quick spray is enough to last the season.

The idea was to deter/kill NF grubs and possibly Swift Moth caterpillars as it is a systemic.  It is a nasty toxic spray containing tiacloprid and should be used with care.

Jennie

[Alan_b]

Jo, I think the best cure for galanthomania is to take yourself off somewhere tropical (or semi-tropical) for the month of February.  Of course that's not necessarily going to save yourself a fortune, you'll just be spending it somewhere else.

[Alan_b]

Jennie, interesting idea to use a systemic insecticide in the hope that it lasts-out the year.  Has anyone else tried this?