In the farm context, a side-dresser is an attachment to a cultivator that
pours a bead of (typically powdered) fertilizer alongside the plant row, on
one or both sides, a couple of inches from the plant, and covers it up.

Ammonium nitrate would be the agricultural nitrogen product. The numbers
are 21-0-0 are the N-P-K percentages, by weight, in the fertilizer. So what
they're using is 21% N (nitrogen) .... and thus it's 79% inert matter,
which might be rock dust, etc. to give you more bulk to work with when
spreading it.

I'd be a bit hesitant to side-dress with a heavy application of this product
as it would tend to burn. Plus it would stimulate vegetative growth at the
expense of fruiting. I'd go with a balanced fertilizer, perhaps 5-5-5 or a
thin application of 10-10-10. It doesn't matter (to me) if that N-P-K ratio
comes from bagged fertilizer or dead fish or composted million dollar
racehorse poopies or whatever.

"MisterMystery" wrote in message
...
This is surely a stupid question. But I found an interesting hint (from
Google Groups) regarding tomato growing, and I don't fully understant it.
That's because english is not my mother tongue.

Maybe someone could explain me the following:

(Quotation
I'll be honest. That is exactly what I do in my home garden and I have
all the tomatoes I want. But we've tested various methods at Extension
and have found that yields are increased significantly with a more
vigorous fertilizing schedule. This is what we do: At the time of
planting we incorporate Osmocote into the soil. Then we spray the
foliage once a week with Miracle Grow. When the plant sets its first
tomatoes, we go back in and side-dress with ammonium sulfate (21-0-0).
Extension's tomatoes out-produce mine by AT LEAST 3 to 1 (really more),
but then I don't need that many tomatoes!!

The part that I don't fully understant is: "we go back in and side-dress
with ammonium sulfate (21-0-0)".
What exactly means "side-dress" (I did not find that expression from my
dictionary)? Do they put ammonium sulfate to ground or do they spray it to
leaves? And what kind of fertilizer is "ammonium sulfate (21-0-0)"? 21 of
what, 0 parts of what and 0 parts of what? I mean, I would understant if
someone would simply say "ammonium sulfate" but what that "21-0-0" means?

And what do you think of that method? (I'm actually sceptical regarding
this
kind of hints. (It's easy to say "3 times better"; depends on what you
compere. And many other factors are likely also involved.) But it's still
interesting to hear all kind of opinions and experiences.)