Question Summary:
What is the minimum age for a girl for her to consumate her marriage with her husband? Is it puberty?

Question Detail:

What is the minimum age for a girl for her to consumate her marriage with her husband? Is it puberty?

Answer :

In the name of Allah, Most Gracious, Most Merciful
Assalaamu `alaykum waRahmatullahi Wabarakatuh
The permissibility of consummating a marriage with a girl is based on her physical strength and not on her age. If consummating the marriage will be injurious to her health then it will not be permissible to do so, although she may have reached the age of puberty. However, if consummating the marriage will not be injurious to her health then it will be permissible to do so, although she may have not reached the age of puberty. (Hashiyya Ibn Aabideen, vol 3, pg 204, HM Sa’eed) 
وقد صرحوا عندنا بأن الزوجة إذا كانت صغيرة لا تطيق الوطئ لا تسلم إلى الزوج حتى تطيقه.
والصحيح أنه غير مقدر بالسن، بل يفوض إلى القاضي بالنظر إليها من سمن أو هزال.
وقدمنا عن التاتر خانية أن البالغة إذا كانت لا تحتمل لا يؤمر بدفعها إلى الزوج أيضا  (حاشية ابن عابدين 3/204)
And Allah knows best
Wassalam
Ml. Talha Desai,
Student Darul Iftaa
Checked and Approved by:
Mufti Ebrahim Desai
Darul Iftaa, Madrassah In'aamiyyah