my stepdad tells me to put metal shavings around the bases of my tomato plants. his reasoning slips my mind, but have any of you heard of this. if so, what's the deal? why is he telling me this? I'm confused...
Never heard of it, but maybe the same reason people suggest to use non-galvanized concrete mesh for tomato cages, rust=iron for the soil and the plants to use?
nope, it just came to me 'duh-vinci' reminded me...isn't it weird how that happens?
anyways, yes, it's for iron. i guess tomatos like lots of iron??? i don't know much about what tomatos like and don't like so ya...he said either metal shavings if ya have em, (got lots of em from work, which is why he said that) or to stick nails around the base of the plant and let em rust for the iron too....
Metals have a high tendency to accumulate in the soil; they are usually very ionized and are thus readily taken into the CEC, but not as easily solubilized by biological forces or as necessary to plant development and therefor hang around. I always hesitate before using maetal products in the garden but have found iron phosphate in a flour and water base to be handy for slugs, and iron toxicities are less likely as it is more readily oxidized and soluble than other metals.
Still I hesitate with shavings because of mechanical damage to worms and such (acknowledged as a two edged sword and there might be up sides there as well) and the unknown composition of metals in "shavings" (new steels and such have a host of other metals as well as iron).
Long story short, I haven't heard of it and am leery, but can't rule it out completely. Use at your own risk.
Are you [url=https://findarticles.com/p/articles/mi_qa3931/is_200205/ai_n9060354/]SURE[/url] you want to add iron?
Perhaps your soil has enough already, and you are not aware. If so you can set up a toxic situation for plants that can actually stunt growth, usually heralded by bronze speckles on the leaves...
This is a good example of where we can try to "outsmart" Nature and just end up messing things up. If you do a test and find you are low on iron (I've RARELY seen it), then there are products to do it safely and without additives like chrome (quick build up and extreme phytotoxicity) that without assays you cannot rule out in a bag of shavings or can of screws.
While I have bored most people here with my steady refrain of "Compost, compost, compost.", it still remains the best way to mitigate any soil deficiency you can name, even water.