By Hank
Cheshire,
United Kingdom 
It's working well - but I'm sure I'm doing it wrone. Lettuce.
About 5 years ago I made a long box, 6ft x 18 ins wide x 6 ins deep. See photo below. I put it on a shelf in my greenhouse, filled it with a mixture of garden soil and multi purpose compost and have been growing lettuce in there ever since.I occasionally throw in a handfull of growmore or chicken pellets but have never changed the soil.
I'm just about to refill it with Winter lettuce seedlings I have ready.
I always get wonderful lettuce but sometimes wonder if it's time to change the soil etc.
26 Sep, 2015
Answers
Yep, entirely agree with Owdboggy - if you start getting problems, that's the time to think about changing the soil and cleaning the container.
26 Sep, 2015
Thanks very much, that's exactly what I hoped you'd say.
26 Sep, 2015
If it ain't broke, don't fix it!
26 Sep, 2015