Compost that sticks together
 

At this time of the year I am sowing a number of seeds in pots in a
slightly warmed (i.e.frost free) greenhouse,prior to pricking them out
into modules.I usually use a mixture of multipurpose (3parts),John
Innes(1 part) and grit sand(1 part).I nearly always obtain good
germination,but inevitably get good germination around the edges of
the pot,but not so good in the centre.The compost (about 2" diameter)
seems to lift up together thus stifling the germinating seeds
underneath.I can sometimes rescue some by shaking the pot to break up
the central stuck compost,and other times water the compost to break
it up.What am I doing wrong?Michael

Compost that sticks together
 

The message

from michael contains these words:

At this time of the year I am sowing a number of seeds in pots in a
slightly warmed (i.e.frost free) greenhouse,prior to pricking them out
into modules.I usually use a mixture of multipurpose (3parts),John
Innes(1 part) and grit sand(1 part).I nearly always obtain good
germination,but inevitably get good germination around the edges of
the pot,but not so good in the centre.The compost (about 2" diameter)
seems to lift up together thus stifling the germinating seeds
underneath.I can sometimes rescue some by shaking the pot to break up
the central stuck compost,and other times water the compost to break
it up.What am I doing wrong?

Overwatering, I'd guess.

And the other thing is using pots instead of trays.

--
Rusty
Growing old is mandatory; growing up is optional.
Direct reply to: horrid dot squeak snailything zetnet point co period uk

Compost that sticks together
 

michael wrote:
At this time of the year I am sowing a number of seeds in pots in a
slightly warmed (i.e.frost free) greenhouse,prior to pricking them out
into modules.I usually use a mixture of multipurpose (3parts),John
Innes(1 part) and grit sand(1 part).I nearly always obtain good
germination,but inevitably get good germination around the edges of
the pot,but not so good in the centre.The compost (about 2" diameter)
seems to lift up together thus stifling the germinating seeds
underneath.I can sometimes rescue some by shaking the pot to break up
the central stuck compost,and other times water the compost to break
it up.What am I doing wrong?Michael

I don't know. I always use 2 parts of multipurpose compost to one part
of sharp sand with good results. It seems to hold moisture well without
getting waterlogged or clogging together.

--
David in Normandy.
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