wrote in message
...
Rod wrote:
There's a lot more to it than the compost, but a premium brand of
general purpose compost is a good place to start (not peat free - I
don't think they've got 'em right for seedlings yet)

I know the peat free is meant to need more attention to feeding, so I
figured it wouldn't be ideal for seeds. But it was also pointed out that
the worm poo and the home compost would both be too nutrient rich for
seeds.
Dunno why they can't handle it, but that's what I was told.
To be honest, it would probably help me more if I could get something that
would help keep the moisture level right!



Seeds contain their own food supply, which is enough to get them through
germination and the production of cotyledons (the first atypical leaves) and
the first 'true' leaves. After this, they need potting on, especially if
grown in a seed tray, so that they have their own small individual pots. At
this point, they can go into a fertilised compost to help boost their
growth.

John Innes compost, for instance is a soil-based compost with a variety of
types:
JI Seed compost is specifically for seeds, having little or no fertiliser;
JI 1 contains low levels of fertiliser;
JI 2 contains higher levels of fertiliser;
JI 3 contains the highest levels of fertiliser.
JI Ericaceous compost is for acid-loving plants like Rhododendrons .....
and I'm sure there are other specialist JI composts, but these are the ones
most often seen.
Many other brands of compost (multi-purpose, peat-free, etc) also have these
choices, so you need to read the label. I prefer to blend JI Seed compost
with another, lighter seed compost and/or grit/perlite to create something
which is more free-draining.

To offer your seeds or resultant seedlings too rich a soil would be like
offering a baby steak and kidney pie, roasties and spinach. They simply
don't need it, couldn't eat it and would be sick if they could! In some
cases, the fertiliser would 'burn' the young plant; in all cases the unused
fertiliser would sour the soil, encourage disease and almost certainly cause
damping-off (a fungal disease which kills seedlings at an astonishing rate).
This is why you're advised to use a fertiliser-free compost.

If you're having trouble with moisture levels, try sprinkling a layer of
fine-grade vermiculite on the top of the soil after sowing. It will help to
retain moisture and will also help to stop the growth of algae on the soil
surface. It is naturally inert and sterile when packed, so should not
introduce disease. It allows light through, so you can even use it on
surface-sown seed.

HTH.

--
Spider
from high ground in SE London,
gardening on clay.