Wow they are growing big... wish mine looked like that. From the look of the first photos you are using straw or something like it for mulch? Any sort of special soil in the beds, what nutrients are they on? And do you have them reticulated or water them manually? If you are travelling I'm guessing it is automated, or you have a very nice "other" to help, like an unusually generous wife or servant child.
Automated watering? No way! Everything is hand watered
In fact, I had some compost tea brewing on Saturday, rolled my ankle that night, and still woke up the next morning and hobbled around the front yard to water the plants.
The "straw" is actually sugar cane mulch. Lucerne mulch is meant to be better, but it breaks down quicker. You could use pea straw mulch, but Bunnings were trying to get rid of some sugar cane mulch that had been removed from their stocklist so I bought about 4 bales.
There is hardly ANY soil in these garden beds. Seriously, there is like 3 bags of soil in each garden bed max. What I did was use the no dig garden technique, also known as lasagne gardening, and that's where you do a layer of hay/straw and a layer of manure alternated until it fills the top. Because I started this in July, the chicken manure had time to settle as it would normally burn the crap out of plants when fresh.
As for nutrients, well it's been a bit of a mixed bag this season. I'm currently using a Guano based product called Phos-Life, but it's pretty expensive. I also built a compost brewer and make some compost tea up every 3 - 4 weeks with worm castings that I have from my 3 worm farms. I also used some stuff called Gogo Juice that you can get from Bunnings, that has a similar principal to compost tea. If you are going to use these microbe based fertilisers you'd be wanting to use rain water, or tap water that's been de-gased so you aren't killing the microbes with the chlorine.
My theory is that these garden beds are nowhere near their peak productivity, as it's going to take another year or two before all the hay & manure is broken down. Just wait until next season!
Hope you don't mind the questions but I'm trying to learn what works for people, especially in Australian conditions, so I can do it.
Go ahead, ask more questions, it was the only way I was able to learn!