[Lesleyk]

 ???Really silly because I should know the answer to this.  However, I have invested in a windowsill propagator this year and I love it.  Have set a few seeds to germinate, mainly perennial flowers, but I am confused.  At what stage do I remove the propagator lids/remove the emerging plants from the propagator?  All the seed packet instructions say the same thing which is basically to keep the seeds in the propagator at a certain temperature until after germination.  They then say to remove the seedlings when large enough to handle and pot on.  But there is a gap.  What do I do once the seeds have germinated but before they are large enough to handle?  Do I remove the lids or remove the trays from the propagator?  Help!  What to do.  By the way, I'm asking this because a lot of the very young seedlings seem to have fallen flat a few days after germination and I'm not sure if this is because I should have done something (like removing lids) or whether other conditions (light/heat) have not been right.  Would welcome any advice.

[Yorkie]

I think the falling over is called 'damping off', which what happens to new seedlings when they are attacked by a fungus at the base of the stem.  Generally caused by too much moisture or humidity, and possibly residual bugs if the seed trays etc weren't fully sterilised.

I take the propagator lid off once the seedlings have appeared, and then let the seedlings grow on in the propagator base until I pot them on as instructed.

[sunshineband]

That is not a silly question at all -- you are right, a key step is missed from the instructions, which Yorkie has identified, and explained.

Once the seedlings are all up, I usually take the tray off the propagator and let the adjust to living in room temperature for a couple of days before potting them on.... with plenty of light of course 

[mumofstig]

Once the seedlings are all up, I usually take the tray off the propagator and let the adjust to living in room temperature for a couple of days before potting them on.... with plenty of light of course 

snap

[Lesleyk]

Do you take the lids off?  Could I, for example, leave the trays on the propagator base (which isn't heated but is self-watering - Garland Super 7), and take the lids off?  As for damping off, I'm disappointed if that is the case because the propagator and trays were brand new and the seed compost ditto, so the only thing I can think of is that the compost is too wet (due to "self watering"), or there wasn't enough light/heat on my windowsill - although that wouldn't account for the fungus necessarily.  Do I need to re-sow all the affected seeds, and if so, is there any advice about how to use the kind of propagator I have for this to avoid damping off in future?  Thanks

[mumofstig]

Yes, take the lids off - once germination has taken place they need less warmth/humidity.

If they were out in the greenhouse I'd put the lids back on at night - but indoors they'll be fine 

[sunshineband]

I am not too sure how these 'self watering' propagators' work, but you do need to make sure that the compost does not remain completely saturated.

I usually give it a good soak before I sow and then cover the seeds with vermiculite, or a very fine sieving of seed compost, which gets a light spray of plain water. This does them for around a week, and then I always water from below, by standing the trays in tepid water in the sink and draining them well before putting them back on the heated section and covering them again.

Even when they have germinated, I still do this as then the little stems do not get splashed etc.

I am sure others manage without this fuff, but it suits me and plants seem to grow OK

[Lesleyk]

According to the instructions, I simply have to keep the bottom tray topped up with water and this will be taken up by the capillary matting on top which in turn will keep the moisture levels in the trays exactly right.  When I sowed the seeds I moistened the compost a bit and, like you, covered the seeds with a thin layer of vermiculite.  This is a process I have followed every year, the only difference this year being the addition of a propagator -  a brand new toy for me.  In the past I have either covered seed trays with glass or put them into plastic bags and kept them on the windowsill that way, with no problems.  So, I guess I will be sowing all these seeds again but I wonder if anyone who has experience of the self-watering propagators could advise on watering or preparation of compost before sowing, or both!!!