I’ve just had a chance to read it. The article is really interesting! I’ve noticed compost seems to go really fast in my garden. During the summer I tend not to bother making a pile per se, but rather just leave pulled weeds in place, because they decompose so quickly anyway. It makes me wonder if I have a similar bacteria.

Basically, the article posits that subterranean strain of bacteria churned up by the nearby volcano, lives in the waterways and is the reason for the fertility of the Chinampas.

Scientists discovered highly heat tolerant bacteria that had excellent composting properties.

Article is fascinating.

David.

Thanks for the clarification – sounds like you live in Chinampasterdam. If it worked for the Aztecs, why not the Dutch?

Our rainfall is about 800mm per year.

Yes, I guess 7.2 is a little high. I even still give the odd handful of lime to fruit trees and soft fruits. I have a meter with a probe, not very accurate, but still gives a pretty good indication of pH. With this I can see widely different readings in different places. A few meters outside my garden I have even had readings as low as 5.5. It is possible the previous gardener used excessive amounts of lime, but I would have thought it would have gone away by now.

Historically Amsterdam was a peat bog, but it’s a long way by now from it’s natural state. Still, for this reason, people often advise me to be sure to use lots of lime in my garden to counter the acidity of the peat.

Managing water levels over the years with dikes and canals has caused the ground to sink. My garden is about 1 meter below sea level, but the original ground is much lower than that, probably another 3-4 meters down. To make the land usable, they’ve filled it in with sand. One of my nearby gardeners said he dug a hole as deep as he could, and about 1.5 meters down he encountered a layer of plastic, probably put there to help keep the ground from settling.

It’s kind of interesting gardening with so much water. The water usually sits about 30-50cm below the garden, meaning plants with roots at least that deep never need any watering. The land is ‘well drained’ so to speak, and the water is always fresh and well circulated. There are of course plants that don’t like wet feet, but most plants seem to cope with it okay. Everything does flood from time to time.

What’s your annual rainfall? What’s the underlying geology where you are? I would have thought a pH of 7.2 was at the high end for the availability of some nutrients. As usual, the plants themselves give a pretty clear indication of any underlying problems. If they look OK, then they probably are.