Mishneh Torah, Blessings 11:9ืืฉื ื ืชืืจื, ืืืืืช ืืจืืืช ืืดื:ืืณ
The blessing shehecheyanu is recited:
[before] fulfilling every mitzvah that we are obligated to fulfill only at a specific time - e.g., shofar, sukkah, lulav, reading the Megillah, and [lighting] Chanukah candles,
[before fulfilling] every mitzvah that involves the acquisition of property - e.g., tzitzit, tefillin, and a guardrail - and
[before fulfilling] every mitzvah that we are obligated to fulfill infrequently - for this resembles a mitzvah we are obligated to fulfill only at a specific time - e.g., circumcising one's son and redeeming him.
If one did not recite the blessing shehecheyanu when making a sukkah or a lulav, one should recite this blessing when fulfilling the mitzvah. The same applies in other similar situations.
[before] fulfilling every mitzvah that we are obligated to fulfill only at a specific time - e.g., shofar, sukkah, lulav, reading the Megillah, and [lighting] Chanukah candles,
[before fulfilling] every mitzvah that involves the acquisition of property - e.g., tzitzit, tefillin, and a guardrail - and
[before fulfilling] every mitzvah that we are obligated to fulfill infrequently - for this resembles a mitzvah we are obligated to fulfill only at a specific time - e.g., circumcising one's son and redeeming him.
If one did not recite the blessing shehecheyanu when making a sukkah or a lulav, one should recite this blessing when fulfilling the mitzvah. The same applies in other similar situations.
Kessef Mishneh on Mishneh Torah, Blessings 11:9:1ืืกืฃ ืืฉื ื ืขื ืืฉื ื ืชืืจื, ืืืืืช ืืจืืืช ืืดื:ืืณ:ืืณ
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