Love it! I remember you posting about this, I am glad it's worked out so well!
I have been doing something similar to your large scale wicking beds, but with 55 gallon drums. Instead of milk crates I use 5 gallon buckets with slits cut into them. I have been favoring peat moss for da wicking qualities and low cost but I want to move away from that.
The blue berry you have might be happier in strait peat moss, by itself or with strawberries, as these are some of the only plants I have found that seem to need really acidic soil.
I would suggest painting your cubes black, to avoid algae growth and improve heat retention, but looking at the bolting that's going on, your cubes must keep plenty of heat!
I look forward to watching more of your videos!
I missed 1 video but I filled it with geotextile fabric and then sand up to the point of the milk crates. Then I added another layer of fabric across the top, the more sand, compost, logs and soil......I would have used only 1 large piece of geotextile fabric but they only make it 6 feet wide at my local store.