Recurring Compost Problem

[Duke Ellington]

This seems to happen every year. I buy multi purpose compost from Homebase. I sieve it and use it for my seeds. Every year I seem to get a green thin moss/algae that forms on the surface of the compost and it seems to stunt the growth of some of my seedlings. My leek seedlings are really suffering this year. Does anyone have any ideas as to what I can do about it?

DUke

[Duke Ellington]

[Tee Gee]

Hi Duke

Thought I would point you in the direction of a thread that was discussed the other day when you were on your jollies:

https://www.allotments4all.co.uk/smf/index.php/topic,80976.0.html

[Duke Ellington]

Thank you TG👍🏻I have read the link and will try to transplant leeks into fresh John Innes. Hopefully they will be okay

DUke

[aquilegia]

Are you watering from above? Better to water from below. Also using grit, perlite or vermiculite to keep the top drier.

[woodypecks]

Yes I would definitely add a bit of perlite to get air into the compost 

[Digeroo]

Are you over watering them?  Not sure I would bother to sieve for large seeds such as leeks.   In fact I do not sieve at all.

[Duke Ellington]

Have now transplanted leeks into JI no1. I had been watering them from below but probably too frequently. The sun dries the surface of my seedling and I stupidly think the whole tray needs watering again. I will try adding perlite when I sow further seeds and see if it makes a difference.
Duke

[Vinlander]

The sun dries the surface of my seedling and I stupidly think the whole tray needs watering again.

Everyone has this problem when they change mix - it's just a question of building up experience.

The quickest learning curve is to get a Ph/Moisture/Light Meter - the square one I have can be bought for £2,3,4 or 5  (the latter from Wilko, with P&P at £4 but free if collected),  there is a round one too - they cover 2 pages on Google Shop.

Cheap and cheerful, but as long as it's working it will prevent mistakes.

Cheers.