Companion planting ? (sort of?)

[garden5]

I've heard several times on this site about "heavy feeders" "nitrogen fixers" etc. I know toms are heavy feeders and beans are nitro fixers, but can someone elaborate on this? What plants suck the nutrients out of the soil and which help it stay (I'm assuming that's what "fixers" are?

I am a new gardener but am a chemist so can give you some insight as to what a N fixer is.

Nitrogen fixation is an essential process of the N cycle when inorganic nitrogen is transformed into organic Nitrogen. This means that compounds such as nitrate, nitrite, ammonia are transformed (normally by N fixers) into organic forms of N. These organic forms are things like peptides, DNA, basically anything that has Carbon and Nitrogen in it is an organic form of N. As humans and pretty mucu every animal we rely on plants to do this conversion for us, since we are not great at doing this for ouselves.

A plant that is a good N fixer basically will just fix a lot of N out of the soil or sometimes even from the air into organic forms. This means that they will be using an awful lot of inorganic nitrogen from the soil to do this, hence why it is important to keep these plants well fertilised. Also very important is the form of N the fertilise is in!! If a plant is a heavy N fixer then it will need a lot of inorganic forms of N fertiliser, things like nitrate, nitrite, ammonia. You would have to look into the specifics of the particular plant to see what form it normally uses.

Hope this helps!!
Gina

Wow, that helps a lot. Thanks!

[garden5]

I've heard several times on this site about "heavy feeders" "nitrogen fixers" etc. I know toms are heavy feeders and beans are nitro fixers, but can someone elaborate on this? What plants suck the nutrients out of the soil and which help it stay (I'm assuming that's what "fixers" are?

I am a new gardener but am a chemist so can give you some insight as to what a N fixer is.

Nitrogen fixation is an essential process of the N cycle when inorganic nitrogen is transformed into organic Nitrogen. This means that compounds such as nitrate, nitrite, ammonia are transformed (normally by N fixers) into organic forms of N. These organic forms are things like peptides, DNA, basically anything that has Carbon and Nitrogen in it is an organic form of N. As humans and pretty mucu every animal we rely on plants to do this conversion for us, since we are not great at doing this for ouselves.

A plant that is a good N fixer basically will just fix a lot of N out of the soil or sometimes even from the air into organic forms. This means that they will be using an awful lot of inorganic nitrogen from the soil to do this, hence why it is important to keep these plants well fertilised. Also very important is the form of N the fertilise is in!! If a plant is a heavy N fixer then it will need a lot of inorganic forms of N fertiliser, things like nitrate, nitrite, ammonia. You would have to look into the specifics of the particular plant to see what form it normally uses.

Hope this helps!!
Gina

Wow, that helps a lot. Thanks!

So, you're saying that not only do nitrogen fixers put nitrogen back into the soil from the air, but they also convert nitrogen that is already in the soil, but in a form unusable to plants, to a form that is usable. Is this right?