Sarracenia problems - anaerobic bacteria?

[jimfoxy]

Hello everyone. I have had a few Sarras these last couple of years that are 'dying'. One was a fantastic S. flava, full of vigour. I split it and they all appeared to do well to begin with but now there is no or a little stunted growth this year and, upon inspecting the roots, there are no new white roots - all the split rhizomes (which were certainly big enough to split) are behaving the same. Parts of rhizomes on some of the plants are also browning. I have no real idea why. No visible pest other than a few scale insect, occasional aphid, slug or caterpillar - can't see anything really tiny moving around.

I grow in an unheated greenhouse and most of my plants thrive. I am thinking the problem is either with the media, anaerobic bacteria, virus or water (well, what else is left?). I use Shamrock moss peat, perlite and (probably) a bit of sand in the media, none of which I wash but all of which I am careful about sourcing.

I suspect my problems are with plants that have recently been split or disturbed (others I have split have been fine, though). (I have one 'Burgundy' which was sold to me as flowering size. What I actually received was a very recently split small piece of rhizome with a flower from the growing point (obviously the flower had established before the rhizome was split) - it certainly was not what I would call 'flowering size' and I still feel conned (don't fall for this one, people!). It did manage to send out a pitcher last year but this year it is sitting there with a few stunted efforts at growth and not much else. Roots don't look good - no new white growth.)

In some of the pots of the ill plants there is a definite smell of rot, but not in all of them. Any tips on how to prevent anaerobic bacteria from settling in? Although I now try to only use water gathered from a clean roof, in the past, I have used water from a felted flat roof where leaves collected and probably caused a higher nutrient level than optimum (TDS checked and still 'ok', though - thinking maybe TDS meter does not show all organic nutrients in water?).

I am wondering whether a really thorough wash of roots to remove all media, and then a repotting might help.

I am also wondering how often experienced Sarra growers out there simply get the occasional plant dying off like this after splitting (I have more than 100 and my problems are with just a small handful).

Thanks for any thoughts. Sorry for the rambling post.

[Alexis]

I scratch my head at sarra deaths sometimes as well Jim.

How big is your greenhouse out of interest? I suspect most problems are caused by lack of air circulation and build up of damp. I sometimes get plants keeling over that have only ever been potted respected growers' own media, so I don't put much emphasis on the quality of the peat or perlite.

I also find problems when topping the water up for the first time in the spring. Doing it very gradually and not having wet peat until the first very warm weather arrives reduces the chance of early rot.

[ada]

Jim, what are the old roots like? o.k for a bit,black/rotten at the ends? any chance of a picture.

Where abouts are they in the greenhouse? all together? far back corner? etc.

ada

[loligo1964]

It strikes me as more of a fungal issue than bacterial. Did you treat the pieces of rhizome with anything when you divided it? It does sound as though your compost has gone anaerobic; and, in which case, it should be changed -- if just to improve oxygenation of the plant roots . . .

[Mike King]

Hi Jim,

I had something like this happen t a lot of my plants in 2006. I ended up repotting everything due to a bad batch of peat.

What mix of peat: perlite are you using? I ause 1:1 and the problems have gone.

[jimfoxy]

Thanks for your ideas, gents. It has spurred me into further investigation!

1) Alexis, thanks for your thoughts. I think ventilation is ok. I don't get too much botrytis in the Winter and I don't think it is a rot/mould problem that is the primary cause of the problem.

2) Ada, see photos below - thanks.

3) Loligo - I usually spray some Chinosol onto the broken surface of the rhizome after splitting. I think you are right in that it is media related.

4) Mike, it appears I put less perlite in than I thought - thanks for the note - I shall increase the amount (time to get the breathing apparatus out). When you say 1:1, I assume you mean by volume?

So my investigation. See below for some photos of a typical suffering plant. I think there is clear evidence of tiny snail/slug damage but I don't think this is the primary problem. There should be plenty of nibbled off new growth if that were the case, and there is no new growth (unless they are also scouring off any new roots?).

I dug out the TDS meter and dipped it in a few things (I think these readings are ppm):

Fresh rainwater in open container: 10-20

Butt rainwater from 'clean' roof: 20

Butt rainwater from flat roof: 30

Water in trays that plants sit in: 40-70

Water in 'death tray' (where I isolate plants that are suffering with this affliction): 150

Interesting, huh? Either the media in those suffering plant pots is bad, or something in them is increasing the TDS level. Originally I had them sitting in trays with others that measured about 50-60. Unfortunately, I cannot remember whether there was anything odd about the media mix I used for them (it was about 2yrs ago). Are the other TDS levels about the same as you get?

Tonight I shall put each component of the media I use into a tray with some water, mix it around and take TDS readings to see if I can glean anything from that.

What I shall definitely do is unpot and wash off all compost from these suffering plants, and put them in fresh (high in perlite) media. I shall also try to empty out all old water from my troughs and replace with completely fresh.

And just to show this is only happening in a minority of cases and that I don't have a greenhouse of death:

Edited June 10, 2010 by jimfoxy

[Alexis]

Nice collection.

I don't think perlite amount is the be all and end all. I've seen very healthy collections in 100% peat and also plants keel over that are in good amounts of perlite.

Have you ever used Westland peat? That is a known source of some problems.

I would also look at the amount of dead matter on the plants. Remember to cut of all the brown bits as soon as possible, and pull dead stems off the rhizome to reveal the log underneath.

[ada]

Jim,looking at the pics of the roots,with the rest of your info.I would say it was a bad batch of peat.When i had it happen the roots looked just like that.

Peat suppliers have already admitted to recycling other compost into their peat,you could have just hit a small pocket of badly mixed stuff.

I did what you are going to do,wash off all the old compost completely,even cut off all the blackened roots and dead foliage,then repot.

If the rhizome is o.k they will recover,they will just look crap for a while.Some usually send up multiple growth points after this.

ada

[John Jearrard]

I had a problem with some compost last year that I still don't quite understand, but I think it started with a storage problem. The bales are stacked outside at my supplier and one of them was very heavy because the wrapper had been slightly damaged and it had got wet. The peat had started to decompose in the plastic wrapping - it gets a slightly greasy feel to it and goes blacker and denser. As a result the mixed compost contains less air and compacts very easily. Once the compost started to shrink, it was infested with an epidemic of compost flies which attacked new roots quite aggressively. Possibly the eggs/larvae were already established in the peat in the bale. I also got a very rapid dense cover of moss on the surface.

Rather like sedge peat, it had become a less suitable potting medium. I don't buy the heavy bales any more.

[Tricky Utrici]

I was one of those that suffered from the Westland "peat" problem. I had a lovely rubricorpora that put up pitchers, at about 45cm they bent backwards and the pitcher tips with young mouths semi open then bent to about 90 degrees, looked like they were screaming then just died back. This looks nothing like that. I have to say that in the pictures there looks to be plenty of green on the plants. If they were mine I'd wash out the roots, re-pot in fresh mixture, put it in a sunny spot, oh and yes talk to them a lot!!

I have one plant that I divided into six in February that I've been worried about, two are fine with good size pitchers, but the others are only now just producing their first shoots.

Tricky

[Alexis]

I still think the harsh winter has had an effect. Some of mine have really been stressed and have been growing twisted pitchers and just phyllodia. I've also got a couple which have gone mad, growing lots of small pitchers as if they've been tissue cultured.

[mattshore]

I dont want to hijack the post but.....

I would also look at the amount of dead matter on the plants. Remember to cut of all the brown bits as soon as possible, and pull dead stems off the rhizome to reveal the log underneath.

I am new to growing Sarra's. Why remove the dead stems off the rhizome? Are they not there to protect the rhizome? There always seem quite a bit of resistance when you try and pull these.

I do find Sarra's growers have very different cultivation techniques (more than other CP's). For example, some say repot every year, others say leave them as long as possible without repotting! Some say remove all growth before winter, others say leave them until spring etc.

[Alexis]

Fungus tends to attack dead material and the problem is when it spreads into living tissue. There's a lot of dead matter on this plant - you can tidy it up by tugging off the dead growth:

[jimfoxy]

1) Thanks for your thoughts everyone. Never used Westland peat, always Shamrock.

I have being doing some TDS testing. I put the same water plus a sample of peat, sand, perlite and John Innes No2 into different containers. I tested TDS over a couple of days:

Start - 12hrs - 36hrs - 48hrs

Water: 20 - 25 - 20 - 20

Perlite: 30 - 35 - 30 - 30

Peat: 110 - 130 - 65 - 70

Sand: 70 - 170 - 190 - 180

John Innes No2: 400 - 520 - 620 - 600

The sand is labelled as 'washed, horticultural grade'. Mmmm, I won't be using it again for bog CPs. Not sure what the peat did; bit odd - maybe something to do with slow water absorption. I probably would have used that sand to repot the plants I am having problems with 1-3yrs ago.

2) Re removing dead growth. I can see it from both angles. Sure, remove absolutely dead rotting vegetation but what about the brown stuff still hanging on quite tightly? If you pull that off and expose the rhizome are you not exposing a fresh surface that can be vulnerable to disease/mould, just like you do when you split the rhizome?

With good ventilation and low levels of moisture, I don't find Botrytis a problem. I see it most on 0-2yr old dense seedlings where it is very very laborious to remove dead growth (and I usually have not the time to do so) and usually I just use a survival of the fittest philosophy and weed out the afflicted as and when I notice through Winter. I figure that some plants will be better at resisting it than others and so should be promoted.

Oh, I am also going to stuff the gaps in my water trays with living sphagnum in an effort to soak up excess nutrient.

Edited June 12, 2010 by jimfoxy

[Mike King]

Hi Jim,

Looking at your mix, you want to really opoen it up with more perlite and even add 3mm granite chips as mentioned before. Alxis is right, remove all dead growth and all the dead leaf bases. Wash the plants to remove any unwanted fungus spores. I have arouind 5,000 plants and every plant is cleaned up periodically so just find the time to do it! Your plants will improve.

[jimfoxy]

Thanks Mike, Alexis. Have repotted them in a more perlite rich mix and pulled off lots of dead material. There actually is a little new growing point activity and the rhizome still looks, for the most part, very healthy. It is just that there are no white roots. Time will tell...

[wallsg7]

Weve all had this happen at some point.Ive found best results by completely changing everything immediately.Repot in a new peat (from a dependable source)with completely new sand or perlite.Also Spray plants with systemic fungicide.Dead leaves left on a plant do not cause an absence of healthy white roots.Your shrivelled black roots are a clear indication that something is seriously wrong.Change everything.