Stagonospora infection - collected threads

[Matt T]

I've been fortunate enough to be able to use Actinovate this past season with three applications since the first autumn storm. I'm afraid I've not conducted any controlled trials and have also changed other aspects of my cultivation regime (i.e. replacing the grit in my potting mix with perlite). However, anecdotally I have noticed a much lower incidence of brown tips on my Narcissus and generally stronger growth. As I say, nothing scientific, but something is definitely better.

[kentish_lass]

About the price of a middle-of-the-road snowdrop.....

That is true Anne and it will make gallons of mix   I wonder if it will kill the Mychorrizal mix we use or vice versa?  I think I will order some too as I am at my wits end and found 6 more staggy pots today in the grit plunge along with other healthy looking pots.  Now I just don't know what to do and have started taking pots out of the plunge and separating iffy looking ones.

Can you 'cleanse' grit of stag?  It cost me a small fortune for all that grit 

[kentish_lass]

(i.e. replacing the grit in my potting mix with perlite).

Matt - I quite like the sound of using Perlite instead of grit as the mix gets very heavy when wet.  I am pleased to hear you are seeing some positive results with the Actinovate, even if its only that they look better.  I am going to bite the bullet and buy some and try to take some photos of before and after.  The trouble is I have been using Carbendazim fungicide as a spray and drench and never marked the pots - I am guessing the fungicide will kill the natural bacterium?

[Alan_b]

Can you 'cleanse' grit of stag?  It cost me a small fortune for all that grit 

I would have thought that putting it in a large pan of water and bringing to the boil or in the oven at over 100C should kill anything.  But perhaps you have too much for that sort of piecemeal treatment?

If you trust eBay, this source of Actinovate is cheaper than the one on Amazon http://www.ebay.co.uk/itm/281124697358 

[Alan_b]

By the way, the new name for Stag. is Peyronellaea curtisii.  Pity about the 'e' because Pyro... would immediately bring to mind the burnt and scorched effect it causes on the leaves.

[Matt T]

Matt - I quite like the sound of using Perlite instead of grit as the mix gets very heavy when wet.

Hi Jennie, I made the change to perlite primarily because I felt that it would provide a lighter potting mix for my bulb collection - lighter in terms of weight as well as a warmer, fluffier, more airy growing medium. I was concerned that grit was contributing to a cold, wet mix, particularly in our very damp climate - the perlite retains air in the mix even when thoroughly wetted. I was worried about making such a drastic change to my method, but so far I cannot report any drawbacks and will continue to use perlite. My standard bulb mix is equal parts perlite, sharp gritty sand and good loam (JI#3 here) with a sprinkle of bonemeal. For snowdrops you might want to add one part organic matter (leaf mould if you have it) but my Galanthus are also doing very well in my standard mix. As this is a rather 'lean' mix, I feed all bulbs regularly - balanced feed early in the season, high potash after flowering onwards (both at half strength, monthly), also occasional doses of seaweed tonic and Actinovate.

...I am guessing the fungicide will kill the natural bacterium?

I would have thought that fungicides should be specific enough in their action that they do not affect bacteria (in the same way that antibiotics don't have an effect on a cold or flu virus), but don't take my word for it. A 2oz sachet has been more than enough for my modest collection - a little goes a long way.

[kentish_lass]

I would have thought that putting it in a large pan of water and bringing to the boil or in the oven at over 100C should kill anything.  But perhaps you have too much for that sort of piecemeal treatment?

If you trust eBay, this source of Actinovate is cheaper than the one on Amazon http://www.ebay.co.uk/itm/281124697358

FAR too much for that treatment Alan!  Like 20-30 sacks of sharp grit and sand at GREAT expense because I thought it was a good move and would keep them safe while I found a piece of ground without swift moth to cover with net in the summer.  I feel I take one step forward and twenty back    I wonder if Jeyes fluid would 'cleanse' the cold frame grit and sand?  Why do they have to keep changing names although Peyroneaella sounds better than Stag !!

Alan I usually trust ebay but not with snowdrops!  However that Actinovate is only 20 grams and not 2 oz which is a big difference.

[Alan_b]

Steve Owen swears by Jeyes Fluid.

[Josh Nelson]

Matt may be right about bacteria being unaffected although I couldn't say myself; what fungicide will generally do is take out the good with the bad - i.e. mycorrhizal fungi will be detrimentally affected (I presume this applies to Actinovate but please anyone advise if they know different).  As these mycorrhizal fungi may be important to plant immunity, health and vigour (I am not sure when it comes to Galanthus but I don't see why they would differ particularly from other plants), I would be hesitant in applying anything with fungicidal action as a wholesale prophylactic (at least where there is not evidence of stag/ Peyronellaea or similar fungal pathogen in an important collection).

Free draining soil rich in organic matter seems to offer the most advantageous soil conditions to wild/ naturalised Galanthus so I try and replicate that with own homemade compost mixed with leaf mould and sharp sand (or just straight into the soil for some as I am on good free draining loam).  No guarantee of course and I am very tempted to get hold of some Actinovate, especially as I currently have a commercial chemical fungicide for spraying/ dunking suspect bulbs.

[kentish_lass]

Josh - I live just up the road from you in West Kingsdown and my soil is very heavy clay with flint.  I have spent 20 years amending most of the garden and found several areas in the garden where the snowdrops grew beautifully for years planted straight into the ground.  Then last year I noticed several were diminishing and dug around and found they were being eaten out of existence by Swift Moth larvae.  The more I dug....the more I found although I still have many in large clumps still growing in the ground.

So, by the time I finished digging clumps of the more expensive cultivars I ended up with many pots to look after.  This was never the way I wanted to grow my snowdrops and now this year some of the pots have stag - it could be the wet weather we have had or it was there last year in its early stages and I never detected it.  I intend to get rid of the soil they are growing in, clean up the bulbs the best I can, repot and wait for the Actinovate to arrive and will not fungicide anymore.   

[Carolyn Walker]

Maggie, Thank you so much for putting all the stag threads together.  Dried elwesii bulbs from the Netherlands purchased last fall and thankfully grown in isolation in pots were completely stag ridden when they emerged now.  I have never had this happen before but recognized it immediately from the forum posts.  Disposed of the whole lot including the pots and the trays, 85 pots!  I think I am done with dried, as opposed to dormant bulbs, because the risks are just too great.

Just ordered Actinovate on Amazon Prime for $21.00.  Arriving Monday.  Has anyone used Serenade, which is another organic fungicide made by Bayer?

[kentish_lass]

Just ordered Actinovate on Amazon Prime for $21.00.  Arriving Monday.  Has anyone used Serenade, which is another organic fungicide made by Bayer?

Carolyn, I was looking at Serenade last night online along with many other natural products.  It seems most are only readily available in the USA - you are lucky as it costs 5 times the price to get them shipped to the UK.

What a shame about all your stag ridden bulbs - it is so distressing to have disease in the collection.  I have thrown several bulbs in the rubbish this week but find it hard to bin the rarer ones I have collected although I feel quite tempted to be honest.  From now on I will be more vigilant with new purchases and use natural products to try and protect them from disease.  Keeping a large collection healthy is not easy 

[Alan_b]

.... Then last year I noticed several were diminishing and dug around and found they were being eaten out of existence by Swift Moth larvae.  The more I dug....the more I found although I still have many in large clumps still growing in the ground.

So, by the time I finished digging clumps of the more expensive cultivars I ended up with many pots to look after.  This was never the way I wanted to grow my snowdrops and now this year some of the pots have stag - it could be the wet weather we have had or it was there last year in its early stages and I never detected it. 

Swift moth larvae burrow around under ground.  Sometimes they will eat an entire bulb and sometimes they move on to another one.  I don't know how they feel about a Stag.-infected bulb.  Maybe the rotted parts don't taste good?  Or perhaps the strong smell identifies the location of the bulb and attracts them? Potentially they could spread the infection around as they move about.

2009 was a very bad year for me.  I had created a raised bed and put all my most precious snowdrops in it.  In 2009 some of them failed to appear, a few had obvious symptoms of stag. and quite a few others started off okay then began to die-back mid season.  Many of these had rotted foul-smelling bulbs and very few roots when I dug them up.  In the end I evacuated everything into pots.  But many of the sick snowdrops did not survive.

I let that bed lie fallow for three years.  During that time quite a number of seedlings appeared but I moved them into pots.  Since 2012 I have been slowly and cautiously repopulating that bed.  I treated it with Trichoderma harzianum for the Stag. and 'Grow-your-own nematodes for the larvae.  In later years I covered the entire bed with a fine insect mesh netting from the end of May to the end of August.  I have not perceived any recurrence of either the Stag. or the larvae problem.

This year I had a yellow-flowered plicatus snowdrop resembling 'Wandlebury Ring' appear.  It was close to where I used to have a bulb of that snowdrop which was last seen in 2008 and failed to show in 2009.  So that is 8 years from one flower to the next.  A photograph from 2014 shows that it was a single leaf then.  Either it is a fortuitous seedling or a small portion of the bulb survived and eventually reconstituted itself over many years.  So don't give up hope, Jennie.             

[Tim Ingram]

I would echo Alan's comments Jennie. And also consider investing your interest in other woodland plants than just snowdrops. It is inevitable that 'monocultures', often of snowdrops selected for looks rather long term garden adaptability will be vulnerable to disease, and we have certainly had similar problems to yours with swift moth caterpillars (they also attack hellebores and many other plants), and recently stagonospora (perhaps exascerbated by the very wet weather last autumn and winter like you say). To some extent the rather inflated value that is put on snowdrops is part of the problem - gardening should be an attempt to tune in to the vageries of the Natural World, not constantly try to hold these at bay. Of course the value also encourages nursery-people like ourselves to want to grow them! Quite a tension there. This thread is certainly useful to us becuse we are trying to build up populations in the garden and at the same time are observing more problems, but these are not restricted to just snowdrops!!

[Matt T]

...It is inevitable that 'monocultures', often of snowdrops selected for looks rather long term garden adaptability will be vulnerable to disease...

This certainly seems to be important. Rather than gathering all the most precious (costly?) ones together, spreading them around in and amongst other plants is a good idea. As well as splitting them up if/as soon as there are enough to plant in different areas so there is a back up. If you have the knack for growing them in pots, an ICU under cover can be useful to mollycoddle a few that need extra attention/protection. Any gardening venture is subject to setbacks, but the price of some snowdrops makes their loss all the more painful. Persevere Jennie and those that stay with you long term will be those you know to be good doers.