What's the point of seed starting compost/potting mix?

[danmow]

I've never understood this but I see seed starting mix, that's purposely low in nutrients, on sale all the time. Does anybody know the reasoning behind using it?

Surely seedlings are going to be hungry for nutrients? Plus am I wrong in assuming that it doesn't mirror what would happen in nature, where most of the rotting organic matter would be on the surface of the soil.

Just curious really.

[WendyC]

I don't think seedlings are hungry when they first germinate as the seed has enough nutrients to start the seedling off with. Seed compost also tends to be finer than MPC. Therefore I use it for small seeds but don't bother with bigger seeds like peas and beans.

[Martin H]

Because the compost is low in nutrients, the seedling tends to make a much bigger root system to seek out the goodness. So when you come to pot them on they can race away.

Like Wendy says, it's less important with bigger seeds that carry all their own nutrients anyway.

[lottie dolly]

I only use MPC,for tiny seeds just sieve very finely,never had a problem,

[Guest]

Because the compost is low in nutrients, the seedling tends to make a much bigger root system to seek out the goodness. So when you come to pot them on they can race away.

Like Wendy says, it's less important with bigger seeds that carry all their own nutrients anyway.

I feel that lower nutrients to start with makes for stronger plants. In all fairness I use MCP for everything, it is only when potting on I add to it. In my mind if you fuss them they become reliant on you.

[sunshinekitty]

seed starting compost is also usually sterilized to prevent the seedling from get mold,damp off another soil born diseases.

[danmow]

Ah I see. So it's more sterile and the absence of nutrients encourages root growth. Fair enough.

[KirstieSparkle]

Interesting! I will probably start using it then I've been using sieved grow bag contents in my seedling trays.
Oh so many things I get wrong lol

[Bigmallly]

Just to be different............I use Mole Hill for seeds & MPC for potting on..........

[KirstieSparkle]

Ohhh now ur just trying extra hard to confuse me!

Where do ppl get all this stuff from. What's the seekrit. Garden centres never have hardly anything.
Ordering stuff online I guess?

[Bigmallly]

Moles are just one of the many beggers I have to put up with................

[danmow]

Interesting! I will probably start using it then I've been using sieved grow bag contents in my seedling trays.
Oh so many things I get wrong lol

I'm still not entirely convinced tbh. I've been reading about Charle's Dowding's no-dig method and he says that it's OK to sow seeds directly into straight compost! Methinks an experiment is in order...

[danmow]

As in the little mole hill soil...? ...I don't get them on my paving stones...which is my whole growing space

[KirstieSparkle]

Hahahaha there I was assuming it was some kind of product or brand.
Thnkfully no moles here.... Yet lol plenty of evil yellow ants though

[Two_Sheds]

I'd never heard of a yellow ant, but you're right, and they like grassy chalkland (we're on sand up here)

BBC Nature - Yellow meadow ant videos, news and facts