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We will all have question like.................what can I use as a alternative to Cheshunt Compound so I thought I would take a look around just to see what other people are doing about this. I received a new book at Christmas from the RHS a year in the garden or something like that. I found this reply on a different forum and thought I would share as it ticks a lot of boxes with regards to DAMPING OFF

Avoiding what causes damping off is the best approach!

Too much water and cool conditions at soil level is the principle cause of damping of.

I minimise the causes as follows;

Sowing: soak seed compost well prior to sowing the seed on it then if the seeds require d
'dark' to germinate spread a light covering of seed compost over the seeds then cover this with a layer of vermiculite or perlite.
This will create a warmish layer at soil level where the seedlings emerge thus reducing the chances of damping off.
If the seeds require ' light' to germinate then omit the compost covering and only place the layer of vermiculite or perlite.
If you have got your watering right you should not need to water again till after germination.
If you require to water seedlings prior to pricking out have a pump spray at hand with a little fungicide (any type) and spray them lightly to keep them going, this should suffice.
If you feel that the tray has dried out ( I.e. It has been too warm) sit the seed tray in a tray of water and dampen the compost from below.
Pricking out; again soak the compost and allow it to drain off before placing the seedling/ s in it.

Sinking the seedling down to the seed leaves can be an advantage as this reduces the area of stem/ root that is most susceptible to rotting (damping off).

Aftercare; again watch the watering, temperatures and ventilation carefully!

Use the hand spray with the fungicide mixture if watering is required prior to the seedling becoming established.

What you want to avoid is cold compost at the point the plant emerges from it, watering makes this area colder than the compost below and the air above which is the main cause of damping off.

You could add a light covering of vermiculite or perlite to the compost surface ( like the commercial people do) as a precaution.

OK I sometimes have seedlings damp off on me but generally when I look at the issue more closely the fault was mine! ..............generally it was down to my watering regime!........... Carelessness/ laziness!

So that's my opinion on the subject!

I for one will be mixing some camomile tea just in case I need it but I will have to find one tea bag as I don't drink tea 


O and the book is called RHS Gardening through the year by Ian Spence published by DK 

ISBN 978-1-4053-4739-6


Ashleigh 2

I have sown bedding Lobelia for the first time this year, it has germinated well and the seedlings are between 1 and 2 cm tall and have no true leaves yet, when should I take the clear plastic lid off the seed tray?



Ashleigh, I open the vents on my lids as soon as the seedlings come up, then wean them off being covered asap

Ashleigh 2

Thanks Fleurisa, I love this forum


Before sowing seed, I water the compost with warm water, when seed has sprouted I whisk off the plastic lid immediately.


is that warm water from the tap if so can you explain why or is it tap water left some where warm over night ??


Mark 499
Hydrogen Peroxide can be used to prevent damping off, cheap & widely available.
Needs diluting to the correct strength though.

Just cold tap water with a little boiling from the kettle. I don't use the stuff from the water butt when planting seeds in case there is bacteria in it; I use it when the plants are a little more robust. I find warm water warms up the potting compost a bit, helping germination.

hollie hock

I like to water the seed trays from the bottom, until you can see the top of the compost change colour, I generally sow on top of this, cover with compost and gently pat down. The compost doesn't seem to get so wet this way and seems a bit more controllable



Overcrowding, overwatering and poor ventilation are usually the worst offenders. If you can keep these under control it's easier to avoid damping off. I think you're right Mike about watering as if they're bigger plants. Lots of people use a spray instead of a can to dampen seedlings. That can help to avoid overdoing the water.


Mike said ".... Please don't waste your time, poncing about sowing indoors/under glass in trays/cells veggie seeds.  Select your outdoor site, prepare the ground, and sow direct..... "

Music to my ears Mike 


Our area by the sea is proving to be very moist, damp conditions for us.  No matter how I ventilate we still seem to suffer.  I have spaced out plants/trays and open doors in the daytime.  It could perhaps be due to temperature but I don't have a heater for the greenhouse so my options here are limited.  

I have noticed some damping off lately affecting some, not all, plants, so today I have removed any affected species/leaves etc and sprinkled the rest with cinnamon.  I hope this will help.  Thanks for the info above.  

Last edited: 15 February 2017 10:57:10


keeping your greenhouse as clean as possible is the best starting point Emma.  In autumn a thorough clean with a disinfectant is essential I think.  Equally, those pots and trays must be washed in strong disinfectant..I use bleach.  And use fresh compost.  Compost needs to be reasonably moist but not wet .and seedlings need space and good ventilation.  

Opening greenhouse door may not be wise.....if the weather is cold your seedlings will suffer.  

Sowing too early is a mistake we all tend to make but later sowings in warmer conditions will cope better. 

Not sure of gh heater can create areas of condensation to the detriment of seedlings. I remember many years ago when we had  an unusually cold winter someone lost all his plants in his heated greenhouse.  In contrast mine surivived in a cold greenhouse.  my plants were kept drier than his were I think !! 

Removing dead foliage and good spacing is all you can do now.  Cheshunt Compound was an excellent product to help prevent damping off but I think this has been discontinued.  Resist the temptation to water repeatedly. 

you dont say what your seedlings are but a later sowing perhaps! 

An alternative to the sterilisation route is including a proportion of garden soil/compost/leafmould in your seed mix, rather than a pure bought compost. This will introduce a range of beneficial/harmless microbes which help to control the species that cause damping off. Weed seed germination can be a problem so this is a better method to use for seeds that germinate quickly and/or larger seeds, plus you need to be able to distinguish your wanted seedlings from any weeds.

Also stick to the other advice above regarding environmental conditions and not sowing too thickly.

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