Seed germination/damping off/Cinnamon

[David Pilling]

Over the years I've lost seedlings to damping off and I've seen seeds rot whilst waiting for them to germinate. For seeds I've been driven to soaking them in domestic antiseptic cleaning liquids - what is called Dettol in the UK, maybe Clorex where you are.

Anyway at this late stage I have become aware that Cinnamon is recommended as a cure for these problems.

[MarkMazer]

Over the years I've lost seedlings to damping off and I've seen seeds rot whilst waiting for them to germinate. For seeds I've been driven to soaking them in domestic antiseptic cleaning liquids - what is called Dettol in the UK, maybe Clorex where you are.

Anyway at this late stage I have become aware that Cinnamon is recommended as a cure for these problems.

Old school... after sowing, sprinkle a thin (1/8 inch/3mm) layer of milled sphagnum moss over the seed pot surface. New school... drench seed pot and/or soak seeds in Daconil (Chlorothalonil), which I understand has been banned in the EU/UK.

Mark Mazer
Hertford, NC
USA

[CG100]

I have always used copper fungicide at sowing. If memory is correct the last that was sold in the UK was copper oxy-choride powder??
It is now illegal in the UK, but Bordeaux mix components and recipes are out there and easily found.
It was banned as it was the Organic "go to" and in some areas (USA only??), it has been used to the extent that the soil now has (phyto-)toxic levels of copper.
A quick mist with copper in a pot.............................................

I have to say that I really have not seen problems with damping-off in bulb seed sowings. Cacti and succulents - a very different story...... very different growth patterns.

Cinnamon? Save it for the apple pie.

[David Pilling]

Cinnamon? Save it for the apple pie.

I was once so convinced by observation of the anti-bacterial properties of cranberry jam (UK) / jelly (USA) that I tried growing orchid seed in it - the seed did not germinate but nor did it suffer from fungal growth.

[CG100]

nor did it suffer from fungal growth.

The sugar alone would achieve that - osmotic pressure.

Soap is a mild disinfectant, dilute bleach also, obviously. The list is almost endless

[MLoos]

There are many chemical fungicides available here in the US, most of which I believe are banned in the UK and elsewhere.  After many trials, copper compounds (copper hydroxide, particularly) have been found to be very effective in controlling damping off.  I don't know about UK availability on that.  There are some organic formulations that are being studied but are not available presently.

Cinnamon, turmeric, oregano (and more) were not reliable.

Quick caveat, I would be very careful using any of the copper compounds.  As with any chemicals, use all personal protection recommendations.  Don't expect the same results for all species.

[CG100]

Bordeaux mix - the original copper fungicide, used on vines - is just copper sulphate and slaked lime (calcium hydroxide), both freely available on EPay in the UK.

I can't remember the original formulation, but it is a substantial excess of slaked lime.

Copper sulphate alone is used at very low concentrations for treating fungus diseases on fish and it will clear algae from small volumes of water outdoors - water butts, patio pools/ponds and suchlike.

[David Pilling]

Back in the good old days we used lots of copper fungicide in the garden to control potato blight.

The sugar alone would achieve that - osmotic pressure.

I presume you're now going to say the mould one gets on jam is on stuff that is not full of sugar, and cranberry is not particularly anti-fungal.

If I knew more science I'd be a better gardener (and jam maker) - at some point I was a scientist, but effects of sec. mod. education and specialisation...

[janemcgary]

Someone mentioned milled sphagnum moss. I used it when I grew Meconopsis (no longer possible since I moved), and it was very effective in keeping the tiny seedlings from damping off, even with the pots covered with very thin plastic (the kind dry-cleaners' bags are made of). It is sold in small bags in good garden centers for use with orchids and other indoor plants. One should not breathe in the particles, however, as it is reported to carry some microorganism dangerous to humans. Another observation on damping off: Calochortus seedlings are very prone to it, so the seed should be sown thinly.

[CG100]

I presume you're now going to say the mould one gets on jam is on stuff that is not full of sugar, and cranberry is not particularly anti-fungal.

Jams are hygroscopic to some degree and form a layer of solution on the surface where there is insufficient sugar concentration to kill bugs, and that is what mould grows in/on.

Salt and sugar both act as preservatives by the same route. Vinegar is a preservative due to pH.

Someone mentioned milled sphagnum moss.

It will work to some degree due to pH, so you'd need to use enough. You'd then have to consider what that low pH would be like for growing particular seedlings/plants.
Many people, me included, prefer to use a JI compost in the UK and that is alkaline (even though the original formulations contained some peat, they were/are made alkaline by addition of lime).

Peat is also in the process of being phased out, ultimately to become illegal to sell and for most horticultural uses in the UK/EU.

[MarkMazer]

"Peat is also in the process of being phased out, ultimately to become illegal to sell and for most horticultural uses in the UK/EU."

Here in the US, we usually don't consider horticultural (milled or long fiber)  "sphagnum moss" as "peat". Does the same thing go in the UK? Will horticultural "spagnum moss" also be phased out?

Mark Mazer
Hertford, NC
USA

[David Pilling]

A vast amount of moss grows on my house (roof and paths) - if I could be bothered I could harvest it. Can't see anyone stopping me.

On Gardeners' World, Friday night, BBC2, the great and good were queuing up to denounce the use of peat, the technique is to claim that you've not used it for 20 or more years. Apparently a lot of peat is still used commercially in the EU for plant production.

But for the likes of me (destined to burn in hell for our gardening sins), 2023 was the first entirely peat free year.

What I get from the DIY store now, is at my level just as good. It is more expensive. Peat was a nice material to touch, so cherish it while you can. I killed plenty of plants using it, but (here comes the excuse) it was easy to obtain.

Anyway if you buy a potted plant at the supermarket you should be very ashamed (they implied).

[janemcgary]

As Mark wrote, milled sphagnum is not peat. It's processed from living sphagnum harvested from nature. Excessive harvesting could damage fragile bogs. I don't know whether that happens. Sphagnum moss can be transplanted into carefully managed bog gardens, but probably the water has to be very pure.
The American view on using peat is different from the British and European, thanks to the existence of Canada (and Alaska) just north of here, with its vast peatlands.
I don't use peat in bulb potting soil because it would be difficult to rehydrate after the summer dry period my bulbs undergo. For the second year now I'm using a purchased "garden topsoil" as the minor organic component; it worked well last year. It was hard to find a product without bark in it, but I did eventually. I do use a little peat in seed-sowing mix.

[Uli]

Hello @janemcgary,

What is your opinion about composted bark? Why do you try to avoid it?
Here in Portugal I had to adapt to new substrates as the ones I was used to in Germany are not available or as import are very expensive.
After some trial and error I finally grow almost all my bulbs except the seedlings in a standardized cheap weed free substrate made 100% of composted bark. It retains a very stable structure for several years, is well aerated and water retentive at the same time but low in nutrients. Which is good because I can fertilize according to the needs of the individual plants. The plants make excellent healthy roots. For some bulbs I mix this substrate with coarse sand.
I have little failures with this compost and generally excellent big bulbs.

[CG100]

The point of banning peat is that it stops damage to peatlands and bogs.
Without seeing it, I am unsure what milled sphagnum might be, but it isn't something that I have ever knowingly seen in the UK, and as it would require damage to habitat to harvest..........

A great many potted plants, as in meant as house-plants, are now potted in coir, but peat is a year or so behind in being banned for commercial use.

I have tried a very few alternatives and the big problem is that they are not composted, so rot/decompose. How quickly depends enormously on how moist/wet they are, mostly. In "ideal" conditions, most alternatives, including the bark that I have tried, can rot down to a small quantity of fine sludge in several months although very often the top 10mm or so remains as it is comparatively dry in many cases.

I have not searched, but one great white hope was milled/composted bracken, but I have never knowingly seen it for sale or heard anything of it for ages.

Huge swathes of the UK has considerable problems with bracken encroachment and it has no real friends - once established it has essentially no major value as/for anything, not least wildlife. Essentialy nothing eats it and it is toxic to varying degrees, and nothing can grow beneath it.
There is just one herbicide that is effective on bracken and that has been banned, and then un-banned, several times but exactly its current status, I have no idea.