What should I do about damping off?

Splandy

I have two windowsill propogators on the go with different seeds in. One of them has hardly germinated, just four seedlings out of twenty four. I thought they might just need a bit more time but when I’ve looked this morning, three of the tiny seedlings have keeled over. It sounds like damping off from what I’ve read. Should I throw these away and assume that all of the seeds inside that propogator are either going to not germinate or have the same infection? The other seedlings are much bigger and healthier but have been kept right next to it, is there any chance of them catching it too?

Lyn

In my opinion it would be better to dump the propagator and let nature sort the seed out.
I grow plants from seeds every year, thousands of them,  I’ve just pricked out 8000 Lobelia seeds into 300 pots, never had a propagator, they bring the plants up quickly, then they can be weak, too damp. You take the lid off the plants keel over. 

If you have anymore seeds just sprinkle them on a small tray of MPC cover with a lid at night if it’s cold and put in a warm place,  some seeds need a sprinkle of vermiculite over some don’t. 
What seeds have you got there now? 

punkdoc

I do use a propagator and find it very useful for plants that need high temperatures to germinate.
To prevent damping off: sow seeds thinly [ too close together encourages damping off ], try not to water the leaves and ensure plenty of air flow, by opening vents during the day, or removing the lid.

Splandy

The seeds that i think have it are ammi. I already showed them a bit late and they haven't germinated well so I've given up and bought some seedlings instead. I think anything that grows now is going to be a bit pathetic. I might try again in Autumn.

the seedlings that seem fine are cosmos, they're not inside the propagator and are on the windowsill but I am worried that they could get it too since they're next to each other. 

It it isn't a heated propagator, it's just a basic one with cells and a lid. They are in a sunny conservatory just out of direct sunlight. It is now very hot in there with this weather, and they've had the lid on during the day still because they hadn't really germinated. Do you think the lid is the problem? I think I might have overwatered too.

punkdoc

Ammi are British natives and don't need heat.
Over watering is also a common problem, soils needs to be just moist, not wet.

Palustris

Try sprinkling cinnamon over the compost, it does help prevent Damping off.

Lyn

punkdoc said:

I do use a propagator and find it very useful for plants that need high temperatures to germinate.
To prevent damping off: sow seeds thinly [ too close together encourages damping off ], try not to water the leaves and ensure plenty of air flow, by opening vents during the day, or removing the lid.

Right Punkdoc,  I don’t grow anything that needs heat to germinate, just annuals for the baskets and tubs and a few to fill in gaps in the borders, the rest are perennials  , so none of that needs heat.