Ring culture in the GH

    This is an old photo of GH2 as pictures speak louder than words. GH2 has been there for 40+ years. 

Its on a concrete base - no soil. There are beds on 3 sides. 

Initially, the beds were lined with clear plastic to hold water, and topped with a layer of gravel.  I grow tomatoes and cucumbers in open bottomed, "ring culture" pots that sit on the gravel beds, sending their roots into the gravel for water. You add feed to the pots but water to the gravel. 
At the end of the season, I've been emptying the soil in the pots onto the gravel. At some point, I cleared out all the gravel and soil and started again, just using a plastic liner and a layer of compost (no gravel). After many years or emptying the old compost into the beds, they are about 6" deep, enough to grow beetroot, lettuce etc in. 

This year, for whatever reason, the tomatoes in GH2 have been very poor and there have been lots of ants in the soil. I've decided to empty the soil out of the bed on the right (the sunny side) and line it with the wool insulation that I'm collecting. This will hold the water. I'll put some coir & compost on top of the insulation then move the supermarket crates (with their seedling salads) into the GH over winter. In spring I'll start again with ring culture pots and hope for a better season next year. 

Does anyone else grow with ring culture?