Can I supply iron rust to the plants through roots in place of Fe?

Question

Can I supply iron rust to the plants through roots in place of Fe?

Answer 1

Iron rust is the most stable form of Fe, so it is very unlikely that plants can get their Fe supply from rust. Anyway, Fe is needed by plants in very small amount so that any amount of it present in the soil in forms other than rust is sufficient. In case of acute Fe deficiency in the soil, you can use any commercial foliar spray formulation containing all the micronutrients.

Answer 2

I have known a few old guys that throw a bunch of old rusty nails in their garden every year. They say it works as a long term iron source to help their plants grow. There has to be something to it because they had been doing it for a lot of years.

Answer 3

Probably not unless you use way too much of it. I have heard that putting nails in the ground with plants was suppose to help. The problem is that rust in it's form is not a readily usable source. Look at the source of the problem. Your soil may be too alkaline; a high pH. That will kill the availability of the element. If so, then even adding a quality iron product would be of little value. Try instead, using poultry manure, especially chicken manure and not hot uncomposted stuff, you need it somewhat composted or purchased a prepared product. This will lower the pH while adding the iron you need. If you want a cheap fix that is organic, use wood ash but only if your pH is low right now. If you have already used lime and used a good amount (and that may be the problem) then do not use wood ash as this will make the pH even higher. And be careful of wood ash because it is a really powerful material and very soluble. Not knowing what plants you have concerns for, you need to find out what pH they like and go from there. Acid loving plants will be better served from manure or blood meal. Alkaline loving plants would do best with wood ash or blood meal. Either way, if you have limed and may have used too much, then go to acidify the soil with manure and no other fertilizer will be needed as this has it all. As a quick note, plants live off of the soil solution, the liquid with the nutrients that have leached into it. The pH of the soil, and resulting pH of that soil solution will determine exactly what nutrients are available and at what levels. If your pH is off from what the plant likes, you will have different nutrient deficiencies depending on the plant. The plant has a pH range that it likes and does best at so that nutrients are available at the right amounts to promote the life processes of the individual.

Answer 4

If you are talking about a small area such as a garden or plants in a greenhouse iron rust works very well, and it is available to plants.  We had some plants growing in wooden flats in the greenhouse a few years ago that were doing poorly.  The plants growing in the corners of the flats were doing great.  We finely figured it out it was because the flats were nailed together at the corners.  We corrected for iron deficiency and out plants were fine. The problem in applying this to large scale agriculture would be getting and applying enough rust.