Horticultural grit or sharp sand

dormouse · Posted: Tue Feb 21, 2012 10:48 pm Post subject: Horticultural grit or sharp sand

Hi - I built a capillary watering bench in my tunnel and it is working fine, But I've noticed that the surface of the compost in some of the pots is getting green (algae or moss of some sort??). I was thinking a layer of grit would stop this. Would that be the best thing to do?
But horticultural grit can be pricey so I was also wondering if a thin layer of sharp sand (from builders providers/ DIY store) would suffice?
Thanks a lot.

michael brenock · Posted: Tue Feb 21, 2012 11:40 pm Post subject:

you will still have the problem with moss and algae, The grit is probably a larger size than builders sand. Appearances are not always the most important .
michael brenock horticultural advisor (retired)

dormouse · Posted: Tue Feb 21, 2012 11:54 pm Post subject:

Thanks Michael. So do you mean the green growth is nothing to worry about? If so, that's good and I can live with it. They are seedlings that will be planted out later.

Greengage · Posted: Wed Feb 22, 2012 10:24 pm Post subject:

If you have moss and Algae growing on the top of compost in the pots its not a problem, If you visit any nursery they all have the same problem before selling on they remove the top layer and redress it with fresh compost, dont worry about it.

dormouse · Posted: Thu Feb 23, 2012 7:30 am Post subject:

Great, thanks a million