Forgot to say “give dew and rain”

What is one supposed to do if, instead of saying “give dew and rain for a blessing” [which is what one has to say in prayer in the wintertime], said “give a blessing” [which is what one has to say in prayer in the summertime]?

Dear …!

The answer to this question depends on when one realized that he made a mistake. There are a few possibilities:

1. If one realized this before finishing the blessing “Bless for us” (the blessing in which this phrase has to be recited), he should recite the words “give dew and rain for a blessing” right away, and continue with the blessing as he always recites it.
2. If one realized this after finishing the blessing “Bless for us”, he should insert this phrase into the blessing “Hear our voice” in this manner: “give dew and rain for a blessing on the face of the earth, for You are a G-d who hears prayers and supplications”, etc.
3. If one realized this after starting the final words of the blessing “Hear our voice”, that is, if he already said the words “Blessed are You” of this blessing, he should conclude the blessing with the words “teach us Your laws” [instead of the regular conclusion “Who hears prayers”]. Then he should say “give dew and rain for a blessing on the face of the earth, for You are a G-d who hears prayers and supplications etc.”, and then conclude this blessing in a regular way [with the words “Who hears prayers”].
4. If one realized this after having finished the blessing “Hear our voice”, but before starting the next blessing “Be favorable”, he should just say the words “give dew and rain”, and then continue on to the blessing “Be favorable”.
5. If one realized this at some point after having finished the blessing “Be favorable”, but before having finished the supplications at the end of the Amidah prayer, he should go back to the blessing “Bless for us”, and continue his prayer from there.
6. If one realized this after having finished the whole Amidah, including the supplications at the end, he should go back to the beginning of the Amidah, and recite the whole prayer over again.

Shulchan Oruch, section Orach Chaim, ch. 117, § 7