How long is it normal to feel recipient area numb?

Your scalp may be numb serval months after your surgery.  In very rare cases it can be permanent.  If you are concerned it is best to see your doctor.

Recipient area feels numb because superficial nerves get damaged during the hair transplant by any of the technique. These usually recover by 3-4 months. 

I consent all my patients for this side effect. 95% of the time the numbness is temporary and normally settles within 6 weeks, sometimes it can take up to 6 months. There is a small proportion of patients who have areas of permanent numbness in the donor and/or recipient area.