old (but unused) seed compost

REMF33 · 10 February

Quick question: can I use last year's seed compost to sow seeds in? Well obviously I can, but is it fine to do so or better not? I know one is not supposed to use old potting compost for new plants in pots as the nutrients leach out, but given seed compost is quite low in nutrients I would guess it doesn't matter.

Fairygirl · 10 February

Seed compost has very little nutrition, which is why it's better for sowing in autumn as opposed to late winter/spring, so that seedlings/plants don't become too big and then leggy. However, it shouldn't matter too much for what you're doing [as you're already thinking] and you'll be able to use a better product, once they're ready for potting on etc. You can even just add a little food if you still have plenty of the compost, once the plants are at the 'going in a 3 inch pot' sort of size.
What you add is also determined by the type of plant itself. For example, you may need to add some grit or Perlite for better drainage

B3 · 10 February

Watch out for slug or snail eggs if the bag has been outside.

REMF33 · 10 February

Thanks, FG. I always prick out into fresh potting compost. I usually buy some 'posh' (expensive) superfine peat free potting compost, as I need relatively little. (Compared to the stupid amounts of potting compost I get through each year.)

Very good point, B3. As you have surmised, it's been outside.

This was kind of an emergency measure, as I thought I would need to sow some aubergine seeds, and I have to send off for the aforementioned posh stuff, but I think now I probably don't, so there's plenty of time to order some before I start sowing proplerly next month. But still good to know.

old (but unused) seed compost

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