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