Backyard Aquaponics
A place to discuss aquaponics

Hi All,
CRTreeDude mentioned the idea of putting "Canary Plants" into our AP systems. "Canary Plants" from the idea of using canaries in coal mines to detect certain (lethal) conditions. Canary Plants would be plants that show signs of nutrient deficiencies easily and early. He mentioned one that liked a certain pH range (the name of which escapes me), and I realized that I was already doing something of the sort. I noticed that my Peace Lily (which puts out leaves very frequently) would sometimes put up a new leaf with signs of iron deficiency (yellow leaf, green veins). I was using that as a signal to add chelated iron to my system. Then the next leaf would look fine. I have actually been watching my Peace Lily carefully and running the system according to it for months. I still test for standard water parameters, but perhaps that's only because I need a few more different Canary Plants.

Beans are another good one for showing iron deficiency rapidly. What other plants are there that we could use as Canaries?

I was wandering around looking into this and found that potatoes might be a good candidate.

This website has a complete listing of what plants look like with various mineral deficiencies. Many of the plants were done on sand so it should be applicable.

http://www.hbci.com/~wenonah/min-def/list.htm

Inreasting but would it not be better to just know the signs for each plant we are growing J.P.?
Being each plant has its own needs.
I see your point if in fact we knew the plant that would show the individual deficiency the soonest we could use that as a signal to incorporate more of this or that.
Just having a plant that would show easily all the mineral deficiencies would not be enough. I
It would have to show them sooner then the rest to be of any use.
Thoughts?
Good link CRT.

That's exactly the point with my Peace Lily. It shows the deficiency before any of my other plants are affected.

Yep - that is the idea - having a sacrifice plant. For example, a fast growing planet will show problems before something else. You don't want to find problems when fruit is setting on, but before. For example, there are certain problems with root crops - nice to see it with radishes instead of Rutabagas. One takes days to grow - the other 3 months.

So canary plant:
1. Must use the same nutrients.
2. Show signs first.